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Filing # 107581617 E-Filed 05/17/2020 03:34:03 PM
IN THE CIRCUIT COURT, NINTH JUDICIAL CIRCUIT, CRIMINAL JUSTICE
DIVISION, IN AND FOR OSCEOLA COUNTY, FLORIDA
STATE OF FLORIDA,
Plaintiff, CASENO.: 2019-CF-003738-A-OS
2018-CF-003532-A-OS
DIVISION: 101
vy.
CHRISTOPHER OTERO-RIVERA,
Defendant.
/
MOTION IN LIMINE TO EXCLUDE CELL GRAPH RECONSTRUCTION MAPS
COMES NOW the Defendant, Christopher Otero-Rivera, by and through the
undersigned counsel files this Motion in Limine, pursuant to the applicable rules of criminal
procedure and moves to exclude cell graphs introduced by Osceola County Sheriff's Office in
this matter. As grounds the defendant would show the Court as follows:
(1) The defendant has been charged by Indictment with Second Degree Murder, a
violation of Fla. Stat. §782.04; Abuse of A Dead Human Body Fla. Stat. §872.06;
and Tampering with Evidence Fla. Stat. §918.13. The exact date of the offense is
unknown, however, allegedly the first parts of her body were recovered on October
24, 2019, “somewhere” on the five (5) acre property located at 3925 Hixon Avenue,
St. Cloud, FL 34772.
(2) The State of Florida, hereinafter the “State,” may attempt to illicit evidence
concerning cell phone towers and mapping in trial.
(3) The defendant, through the undersigned attorney, requests that the State be
prohibited from eliciting testimony from Donna Sita, Crime Scene Analyst
Supervisor, hereinafter “Sita” from the Osceola County Sheriff's Office, concerning
cell phone towers and mapping which amounts to cell phone tracking.
(4) The State’s proposed cell-site expert testimony from Sita is insufficient and
unreliable to be admitted under Fla. R. of Evid. §90.702. Accordingly, this Court
should exclude this evidence pursuant to Fla. R. of Evid. §90.401 and Fla. R. of
Evid. §90.403 because such evidence is not relevant and even if it is found relevant
its probative value is outweighed by the danger of undue prejudice.FLORIDA RULES OF EVIDENCE §90.702
The testimony concerning cell phone towers and mapping known as cellphone tracking
should be excluded pursuant to Fla. R. of Evid. 90.702 and 702. The rule provides that a
“witness who is qualified as an expert may testify in the form of an opinion:
“Tilf the scientific, technical, or other specialized knowledge will assist the trier of fact
in the understanding of the evidence or in the determining a fact in issue, a witness
qualified as an expert by knowledge, skill, experience, training, or education may testify
about it in the form of an opinion or otherwise if:
(1) The testimony is based on sufficient facts or data;
(2) The testimony is the product of reliable principles and methods; and
(3) The witness has applied the principles and methods of reliability to the facts
of the case.
The State of Florida has abandoned the Frye standard for admissibility and for purposes
of substantive challenges of scientific evidence has adopted the analysis espoused in Daubert v.
Merrell Dow Pharmaceuticals, 509 U.S. 579 (1993). The Court should also look to Federal R.
Evid 702 which reads:
(1) the expert’s scientific, technical, or other specialized knowledge will help
the trier of fact to understand the evidence or to determine a fact in issue;
(2) the testimony is based on sufficient facts or data;
(3) the testimony is the product of reliable principles and methods; and
(4) the expert has reliably applied the principles and methods to the facts of the
case.
This Court must make a preliminary, assessment of “whether the reasoning or
methodology underlying the testimony is scientifically valid’ and whether that reasoning or
methodology properly can be applied to the facts at issue.” Id. at 592-593. The proponent of
the testimony bears the burden of proving that the proffered testimony meets the requirements.
Here, the State has failed to meet that burden with Sita’s proposed testimony.
1 |t cannot be said to be “scientifically valid” if the data can be manipulated or altered. “Validity” in its purest
form, refers to the how a scientific test or piece of research actually measures what it sets out to, or how well it
reflects what it purports to be. If the examiner can manipulate the outcome there is no “validity” hence no
reliability.Sita’s methodology is not scientifically valid and therefore not reliable. An expert
witness may offer “expert testimony only if the trial judge finds that the witness’s qualifications
and methods make his opinion ‘reliable.” United States v. Smith, 640 F.3d 358, 365 (D.C. Cir.
2011). Here, the proposed expert testimony and report are not reliable. Sita’s reports, graphs
and maps are based upon a theory called “Granulization” which relies on the faulty assumption
that a cell phone connects to the closest cell tower at the time a call is placed.
The theory is based upon the idea that the “expert” can demonstrate the area covered by
a cell phone by drawing circles or pie shapes on a map where the circles represent the
approximate coverage area of a cell tower and that the cell phone will connect to the closest
tower nearly one hundred percent of the time. The basis for the theory is that the cell towers
are sectorized, meaning that a cell tower has more than one antenna, that each antennas points
in a compass direction defined in degrees, and that the analyst can determine how far those
signals reach based on comparing the locations of the adjacent cellular towers.
One of the many fimndamental flaws in this theory is that it relies on the premise that a
cell phone always connects to the cell tower that is closest and this is simply not true. Cell
phones always connect with the tower emitting the strongest signal at a given moment, not the
closest. Sita’s proposed maps and testimony seems to rely on this faulty assumption that a
cellphone connects to the nearest cell tower. However, the actual determination of which cell
tower is used is complex and hinges on a multitude of factors that are not memorialized in the
call detail records. There is no data provided to determine why that particular tower was used
for the call. The question of how a signal is transmitted by a cell phone is selected by a
particular cell tower is purely a question of science and engineering. Many factors come into
play in the selection of a tower to handle a cellular phone call, and these factors are specific to
the moment in time when the call is connected. Such factors include: (1) the loading of the
towers in the area, which means, which tower has the available capacity at that moment in time
to handle the call; (2) the health of the towers in the area at the moment in time, which means,
are all towers fully functioning at the time of the call; (3) the line of sight to the tower from the
cellular phone itself; (4) the radio signal interference from current weather conditions that can
cause fade of the signal (attenuation); (5) the condition, make and model of the particular cell
phone being used; (6) the amount of interference in the area from other towers; (7) the multi-
pathing which is a function of the terrainas well as both natural and man-made clutter in the area such as trees, hills, buildings and signs
that cause radios waves to be either reflected or absorbed, also referred to as Rayleigh fading;
(8) the strength and quality of signal from the towers around the cell phone; and (9) whether the
phone is inside a building or outside at the time the call was recorded, where structural material
may block the signal from one tower, forcing the cell phone to select a different tower than one
it would be able to connect with if it were outdoors.
Under Granulization Theory, there are four ways to determine the approximate
coverage area of a cell tower antenna sector: (1) using a standard radius from the tower to the
edge of the coverage area: (2) drawing the circles on the map after plotting the locations of cell
towers where the circles are drawn to overlap each other based on the distance between the cell
towers; (3) the compass direction of the tower antenna used for a phone call; and (4) the beam
width of the radio signal projected by the sector antenna. This theory fails to meet the reliability
standard under Daubert because there is no accepted scientific methodology used in this
process, there is no method for calculating known error, there is no recognized community of
peers that accepts this method as being a “scientific method” or even a “forensic science,” there
is no empirical data to support such analysis, and there are no standards set by any governing
body that establishes a method or standardization of this type of analysis.
Sita’s proposed testimony, maps, and reports do not meet the requirements defined in
Fla. R. of Evid. §90.702. First, the testimony is not based upon sufficient facts or data. There
is no fact basis for drawing coverage circles or pie shapes on a map by Sita, and the cellular
company does not provide such data to experts in cases. The physical location of the cell
towers is factual in basis because cellular carriers maintain geo-location (GPS) coordinates of
cell towers and provide those GPS locations to the expert for use in his plotting of the locations
of the towers. However, data regarding the actual coverage area of any tower at the time of the
incident is not provided by the cellular carrier and no method exists which can determine the
coverage of a cell tower at the time of the incident based on historical call detail records. It is
not possible to reliably determine the coverage area of a cell tower antenna as it relates to a
particular cell phone at the time of call.
Second, the testimony is not the product of reliable principles and methods. There is no
published set of principles or methods governing the estimation of cell tower coverage based on
simply drawing circles on a map where the circles overlap and or the size of the circles aredetermined by the distance between cell towers. In fact, the distance between cell towers on a
map have no real bearing on the coverage area of the cell tower at all for the following reasons:
a. cell towers are placed based on anticipated load, which is the maximum number of
cell phone calls anticipated at peak load times for the cell tower. Thus, the expected
coverage area can vary widely between cell towers.
b. Cell towers are not always configured to provide the same amount of antenna power
output, which determines the maximum range of the signal produced by the
antennas.
c. Cell towers are placed to cover specific areas by either mechanically or
electronically tilting the antennas toward the ground and are not configured to cover
an area shown as a perfect circle on a map.
d. Not all tower antennas have the same beamwidth. Beamwidth is the width of the
antenna signal defined in degrees. The most widely used analogy to describe
beamwidth is to think of an antenna as projecting a beam of light, in the same way
that a flashlight beam projects. As the beam exits the flashlight it spreads out in a
attern. In the same way that some flashlights can adjust the width of the beam
light to become wider or narrower, the antennas on a cell tower can be adjusted to
roject a wider or narrower beam of radio signals.
e. Each cell tower that contains sector antennas can have 2 or more of these antennas
jointing in different compass directions. Each of the antennas can be configured
independent of the other antenna to suit the coverage need for that particular tower.
In other words, the antennas can each have a different down tilt, beamwidth and a
specified direction for the antenna. While the azimuth, which is the direction the
antenna points, may be provided in the tower locations records, the actual coverage
area of the sector antenna can vary widely even between sector antennas on the
same tower mast.
f. In today’s cellular system environment, many cell towers contain more than a single
set of antennas for a carrier, making it even more difficult to use the standard three
sector antenna idea to estimate the coverage area.
Third, Sita has not applied the principles and methods reliably to the facts of the case as
there are no principles or methods to determine the coverage area of a cell tower or cell tower
5sector based simply on the location of cell towers without applying complex engineering
formulae to known parameters for each cell tower sector antenna, it is not possible for anyone
to
reliably determine the particular coverage area of a cell tower or cell tower antenna after the
fact based solely on historical cell tower location data or historical call detail records. Even if
such mathematical formulae were used to “predict” the coverage area, it is well known that
these prediction maps are not perfect, and that they are used only to “estimate” where a cell
phone would receive a signal if all of the conditions in the mathematical model are perfectly
aligned to the actual conditions at the time the call is being made.
While in some cases, law enforcement agents may perform a “drive test” to show the
coverage area of a cell tower antenna sectors, these drive tests are not reliable. Drive test are
not performed close to the actual time that any of the cell phone calls were recorded in the
historical call detail records. The drive testing equipment and methods are not designed or used
for the purpose of forensically determining the coverage area of cell towers and, unless the
exact same conditions are present at the time of the drive test to match the conditions at the
time a phone call was recorded, it is impossible to say that there is a 1 to 1 correlation to the
shape of the tower coverage at the time of the drive test and the time of any particular phone
call record. Moreover, due to the dynamic nature of conditions surrounding any particular cell
tower at the time of a drive test, unless multiple drive tests are performed and the data is
analyzed in an empirical fashion, it is not a reliable method for determining the tower antenna
coverage at the time ofa particular phone call. Finally, drive testing technology is not designed
for the purpose of analyzing historical events, but it is designed for measuring the coverage and
health of a cellular tower equipment at the time the drive test is conducted and has no relevance
to the coverage and health of cellular tower equipment that was present at some point in the
past.
FLORIDA RULES OF EVIDENCE 90.401
The cell tower evidence should be excluded because it is not relevant. The
government’s cell tower tracking evidence also fails to satisfy the threshold of relevance. “Rule
702 further requires that the evidence or testimony assist the trier of fact to understand the
evidence or to determine a fact in issue.” This condition goes primarily to relevance.” Daubert.
509 US. at 591.
As the proponent of the cell tower tracking evidence, the government must prove the
6preliminary fact that a connection of a cell phone to a particular tower is relevant. In order to
inculpate the Defendant by offering the connections of various cell phones with various towers
as circumstantial evidence of Nicole Montalvo’s, hereinafter “Montalvo” location prior to her
disappearance the government must prove the preliminary fact that there is a repeatable nearly
1:1 causal correlation of the cell phones signals being routed to geographically the nearest
tower. Otherwise, what tower
connects with the cellular phone call is irrelevant, and the use of a cell tower connection to
prove Nicole Montalvo’s location would be grossly and dangerously misleading to the trier of
fact. The jury necessarily would speculate whether a cell phone always connects with the
closest cell tower, or whether a cell phone may connect for a myriad of technical reason with
another cell tower. To allow such speculation violates the Due Process Clause of the United
States Constitution.
As discussed above, the science involved does not support the proposition that a cell
phone repeatedly connects to the nearest tower with any scientific level of accuracy or
reliability. Moreover, the manner in which Sita draws pie wedge and circle shapes with arrows
on a map pursuant to the granulization theory is not scientifically valid. Evidence that a
particular cell phone connected with a particular tower does not tend to “prove or disprove a
material fact.” and therefore fails to satisfy the threshold relevance inquiry and should not be
submitted to the jury for its consideration. Fla. R. of Evid. 90.401.
FLORIDA RULES OF EVIDENCE 90.401
The probative value of the cell tower evidence is substantially outweighed by the
danger of unfair prejudice. Fla. R. of Evid. §403 excludes an expert’s testimony if “its
probative value is substantially outweighed by the danger of unfair prejudice, confusion of
issues, misleading the jury, or needless presentation of cumulative evidence.” Expert testimony
carries risks of violating Rule 403 because it can be powerful and misleading, and thus difficult
to evaluate. Daubert, 509 U.S. at 595. Due to this risk, it is important for this Court to
carefully weigh the probative value of CST Sita’s proposed testimony under Rule §403. Id. at
595. This raises an important question of admissibility, not just one of weight. Here the
government is seeking to introduce expert testimony that uses the cell site data to place
Montalvo near certain locations such as her home, the homes of others, and various locations in
and around St. Cloud, FL. The State has put forth draft reports with precise pie wedges shapes
7drawn in a compelling manner to try to prove Montalvo was in certain key locations at specific
times. However, the actual methodology (or lack thereof) behind these plotted maps does not
support that conclusion. There is a serious danger of unfair prejudice that far outweighs their
probative value and they should be excluded.
CONCLUSION
For all the reasons set forth in this motion, Mr. Otero-Rivera, respectfully requests that
this Court exclude any and all testimony of CST Sita regarding the cellular analysis conducted
in this matter, as well as the associated maps and reports of CST Sita. Mr. Otero-Rivera further
request a hearing on this matter so that he may have the opportunity to demonstrate to the Court
that CST Sita’s conclusions are not reliable and therefore should not be admissible.
CERTIFICATE OF SERVICE
I] HEREBY CERTIFY that a true and correct copy of the foregoing has been E-filed
thru the E-file Portal System to the State Attorney’s Office, rwilliams@saoS5.org and
JMcManus@saoS.org; on this 16" day of May, 2020.
oN
“ )
om
VA a ce
[Aa doh kc -
U ss
Migdalia Perez, Esq.,
FBN: 696307
517 Bryan Street
Kissimmee, FL 34741
407.530.4920 Office
407.540.9351 Fax
mperez@perezlasurelaw.com
By:
KIMBERLY A. LaSURE
Florida Bar No. 883751517 Bryan Street
Kissimmee, FL 34741
407.530.4920 Office
407.540.9351 Fax
Klasure@perezlasurelaw.com
Preview
Filing # 107581617 E-Filed 05/17/2020 03:34:03 PM IN THE CIRCUIT COURT, NINTH JUDICIAL CIRCUIT, CRIMINAL JUSTICE DIVISION, IN AND FOR OSCEOLA COUNTY, FLORIDA STATE OF FLORIDA, Plaintiff, CASENO.: 2019-CF-003738-A-OS 2018-CF-003532-A-OS DIVISION: 101 vy. CHRISTOPHER OTERO-RIVERA, Defendant. / MOTION IN LIMINE TO EXCLUDE CELL GRAPH RECONSTRUCTION MAPS COMES NOW the Defendant, Christopher Otero-Rivera, by and through the undersigned counsel files this Motion in Limine, pursuant to the applicable rules of criminal procedure and moves to exclude cell graphs introduced by Osceola County Sheriff's Office in this matter. As grounds the defendant would show the Court as follows: (1) The defendant has been charged by Indictment with Second Degree Murder, a violation of Fla. Stat. §782.04; Abuse of A Dead Human Body Fla. Stat. §872.06; and Tampering with Evidence Fla. Stat. §918.13. The exact date of the offense is unknown, however, allegedly the first parts of her body were recovered on October 24, 2019, “somewhere” on the five (5) acre property located at 3925 Hixon Avenue, St. Cloud, FL 34772. (2) The State of Florida, hereinafter the “State,” may attempt to illicit evidence concerning cell phone towers and mapping in trial. (3) The defendant, through the undersigned attorney, requests that the State be prohibited from eliciting testimony from Donna Sita, Crime Scene Analyst Supervisor, hereinafter “Sita” from the Osceola County Sheriff's Office, concerning cell phone towers and mapping which amounts to cell phone tracking. (4) The State’s proposed cell-site expert testimony from Sita is insufficient and unreliable to be admitted under Fla. R. of Evid. §90.702. Accordingly, this Court should exclude this evidence pursuant to Fla. R. of Evid. §90.401 and Fla. R. of Evid. §90.403 because such evidence is not relevant and even if it is found relevant its probative value is outweighed by the danger of undue prejudice.FLORIDA RULES OF EVIDENCE §90.702 The testimony concerning cell phone towers and mapping known as cellphone tracking should be excluded pursuant to Fla. R. of Evid. 90.702 and 702. The rule provides that a “witness who is qualified as an expert may testify in the form of an opinion: “Tilf the scientific, technical, or other specialized knowledge will assist the trier of fact in the understanding of the evidence or in the determining a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training, or education may testify about it in the form of an opinion or otherwise if: (1) The testimony is based on sufficient facts or data; (2) The testimony is the product of reliable principles and methods; and (3) The witness has applied the principles and methods of reliability to the facts of the case. The State of Florida has abandoned the Frye standard for admissibility and for purposes of substantive challenges of scientific evidence has adopted the analysis espoused in Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579 (1993). The Court should also look to Federal R. Evid 702 which reads: (1) the expert’s scientific, technical, or other specialized knowledge will help the trier of fact to understand the evidence or to determine a fact in issue; (2) the testimony is based on sufficient facts or data; (3) the testimony is the product of reliable principles and methods; and (4) the expert has reliably applied the principles and methods to the facts of the case. This Court must make a preliminary, assessment of “whether the reasoning or methodology underlying the testimony is scientifically valid’ and whether that reasoning or methodology properly can be applied to the facts at issue.” Id. at 592-593. The proponent of the testimony bears the burden of proving that the proffered testimony meets the requirements. Here, the State has failed to meet that burden with Sita’s proposed testimony. 1 |t cannot be said to be “scientifically valid” if the data can be manipulated or altered. “Validity” in its purest form, refers to the how a scientific test or piece of research actually measures what it sets out to, or how well it reflects what it purports to be. If the examiner can manipulate the outcome there is no “validity” hence no reliability.Sita’s methodology is not scientifically valid and therefore not reliable. An expert witness may offer “expert testimony only if the trial judge finds that the witness’s qualifications and methods make his opinion ‘reliable.” United States v. Smith, 640 F.3d 358, 365 (D.C. Cir. 2011). Here, the proposed expert testimony and report are not reliable. Sita’s reports, graphs and maps are based upon a theory called “Granulization” which relies on the faulty assumption that a cell phone connects to the closest cell tower at the time a call is placed. The theory is based upon the idea that the “expert” can demonstrate the area covered by a cell phone by drawing circles or pie shapes on a map where the circles represent the approximate coverage area of a cell tower and that the cell phone will connect to the closest tower nearly one hundred percent of the time. The basis for the theory is that the cell towers are sectorized, meaning that a cell tower has more than one antenna, that each antennas points in a compass direction defined in degrees, and that the analyst can determine how far those signals reach based on comparing the locations of the adjacent cellular towers. One of the many fimndamental flaws in this theory is that it relies on the premise that a cell phone always connects to the cell tower that is closest and this is simply not true. Cell phones always connect with the tower emitting the strongest signal at a given moment, not the closest. Sita’s proposed maps and testimony seems to rely on this faulty assumption that a cellphone connects to the nearest cell tower. However, the actual determination of which cell tower is used is complex and hinges on a multitude of factors that are not memorialized in the call detail records. There is no data provided to determine why that particular tower was used for the call. The question of how a signal is transmitted by a cell phone is selected by a particular cell tower is purely a question of science and engineering. Many factors come into play in the selection of a tower to handle a cellular phone call, and these factors are specific to the moment in time when the call is connected. Such factors include: (1) the loading of the towers in the area, which means, which tower has the available capacity at that moment in time to handle the call; (2) the health of the towers in the area at the moment in time, which means, are all towers fully functioning at the time of the call; (3) the line of sight to the tower from the cellular phone itself; (4) the radio signal interference from current weather conditions that can cause fade of the signal (attenuation); (5) the condition, make and model of the particular cell phone being used; (6) the amount of interference in the area from other towers; (7) the multi- pathing which is a function of the terrainas well as both natural and man-made clutter in the area such as trees, hills, buildings and signs that cause radios waves to be either reflected or absorbed, also referred to as Rayleigh fading; (8) the strength and quality of signal from the towers around the cell phone; and (9) whether the phone is inside a building or outside at the time the call was recorded, where structural material may block the signal from one tower, forcing the cell phone to select a different tower than one it would be able to connect with if it were outdoors. Under Granulization Theory, there are four ways to determine the approximate coverage area of a cell tower antenna sector: (1) using a standard radius from the tower to the edge of the coverage area: (2) drawing the circles on the map after plotting the locations of cell towers where the circles are drawn to overlap each other based on the distance between the cell towers; (3) the compass direction of the tower antenna used for a phone call; and (4) the beam width of the radio signal projected by the sector antenna. This theory fails to meet the reliability standard under Daubert because there is no accepted scientific methodology used in this process, there is no method for calculating known error, there is no recognized community of peers that accepts this method as being a “scientific method” or even a “forensic science,” there is no empirical data to support such analysis, and there are no standards set by any governing body that establishes a method or standardization of this type of analysis. Sita’s proposed testimony, maps, and reports do not meet the requirements defined in Fla. R. of Evid. §90.702. First, the testimony is not based upon sufficient facts or data. There is no fact basis for drawing coverage circles or pie shapes on a map by Sita, and the cellular company does not provide such data to experts in cases. The physical location of the cell towers is factual in basis because cellular carriers maintain geo-location (GPS) coordinates of cell towers and provide those GPS locations to the expert for use in his plotting of the locations of the towers. However, data regarding the actual coverage area of any tower at the time of the incident is not provided by the cellular carrier and no method exists which can determine the coverage of a cell tower at the time of the incident based on historical call detail records. It is not possible to reliably determine the coverage area of a cell tower antenna as it relates to a particular cell phone at the time of call. Second, the testimony is not the product of reliable principles and methods. There is no published set of principles or methods governing the estimation of cell tower coverage based on simply drawing circles on a map where the circles overlap and or the size of the circles aredetermined by the distance between cell towers. In fact, the distance between cell towers on a map have no real bearing on the coverage area of the cell tower at all for the following reasons: a. cell towers are placed based on anticipated load, which is the maximum number of cell phone calls anticipated at peak load times for the cell tower. Thus, the expected coverage area can vary widely between cell towers. b. Cell towers are not always configured to provide the same amount of antenna power output, which determines the maximum range of the signal produced by the antennas. c. Cell towers are placed to cover specific areas by either mechanically or electronically tilting the antennas toward the ground and are not configured to cover an area shown as a perfect circle on a map. d. Not all tower antennas have the same beamwidth. Beamwidth is the width of the antenna signal defined in degrees. The most widely used analogy to describe beamwidth is to think of an antenna as projecting a beam of light, in the same way that a flashlight beam projects. As the beam exits the flashlight it spreads out in a attern. In the same way that some flashlights can adjust the width of the beam light to become wider or narrower, the antennas on a cell tower can be adjusted to roject a wider or narrower beam of radio signals. e. Each cell tower that contains sector antennas can have 2 or more of these antennas jointing in different compass directions. Each of the antennas can be configured independent of the other antenna to suit the coverage need for that particular tower. In other words, the antennas can each have a different down tilt, beamwidth and a specified direction for the antenna. While the azimuth, which is the direction the antenna points, may be provided in the tower locations records, the actual coverage area of the sector antenna can vary widely even between sector antennas on the same tower mast. f. In today’s cellular system environment, many cell towers contain more than a single set of antennas for a carrier, making it even more difficult to use the standard three sector antenna idea to estimate the coverage area. Third, Sita has not applied the principles and methods reliably to the facts of the case as there are no principles or methods to determine the coverage area of a cell tower or cell tower 5sector based simply on the location of cell towers without applying complex engineering formulae to known parameters for each cell tower sector antenna, it is not possible for anyone to reliably determine the particular coverage area of a cell tower or cell tower antenna after the fact based solely on historical cell tower location data or historical call detail records. Even if such mathematical formulae were used to “predict” the coverage area, it is well known that these prediction maps are not perfect, and that they are used only to “estimate” where a cell phone would receive a signal if all of the conditions in the mathematical model are perfectly aligned to the actual conditions at the time the call is being made. While in some cases, law enforcement agents may perform a “drive test” to show the coverage area of a cell tower antenna sectors, these drive tests are not reliable. Drive test are not performed close to the actual time that any of the cell phone calls were recorded in the historical call detail records. The drive testing equipment and methods are not designed or used for the purpose of forensically determining the coverage area of cell towers and, unless the exact same conditions are present at the time of the drive test to match the conditions at the time a phone call was recorded, it is impossible to say that there is a 1 to 1 correlation to the shape of the tower coverage at the time of the drive test and the time of any particular phone call record. Moreover, due to the dynamic nature of conditions surrounding any particular cell tower at the time of a drive test, unless multiple drive tests are performed and the data is analyzed in an empirical fashion, it is not a reliable method for determining the tower antenna coverage at the time ofa particular phone call. Finally, drive testing technology is not designed for the purpose of analyzing historical events, but it is designed for measuring the coverage and health of a cellular tower equipment at the time the drive test is conducted and has no relevance to the coverage and health of cellular tower equipment that was present at some point in the past. FLORIDA RULES OF EVIDENCE 90.401 The cell tower evidence should be excluded because it is not relevant. The government’s cell tower tracking evidence also fails to satisfy the threshold of relevance. “Rule 702 further requires that the evidence or testimony assist the trier of fact to understand the evidence or to determine a fact in issue.” This condition goes primarily to relevance.” Daubert. 509 US. at 591. As the proponent of the cell tower tracking evidence, the government must prove the 6preliminary fact that a connection of a cell phone to a particular tower is relevant. In order to inculpate the Defendant by offering the connections of various cell phones with various towers as circumstantial evidence of Nicole Montalvo’s, hereinafter “Montalvo” location prior to her disappearance the government must prove the preliminary fact that there is a repeatable nearly 1:1 causal correlation of the cell phones signals being routed to geographically the nearest tower. Otherwise, what tower connects with the cellular phone call is irrelevant, and the use of a cell tower connection to prove Nicole Montalvo’s location would be grossly and dangerously misleading to the trier of fact. The jury necessarily would speculate whether a cell phone always connects with the closest cell tower, or whether a cell phone may connect for a myriad of technical reason with another cell tower. To allow such speculation violates the Due Process Clause of the United States Constitution. As discussed above, the science involved does not support the proposition that a cell phone repeatedly connects to the nearest tower with any scientific level of accuracy or reliability. Moreover, the manner in which Sita draws pie wedge and circle shapes with arrows on a map pursuant to the granulization theory is not scientifically valid. Evidence that a particular cell phone connected with a particular tower does not tend to “prove or disprove a material fact.” and therefore fails to satisfy the threshold relevance inquiry and should not be submitted to the jury for its consideration. Fla. R. of Evid. 90.401. FLORIDA RULES OF EVIDENCE 90.401 The probative value of the cell tower evidence is substantially outweighed by the danger of unfair prejudice. Fla. R. of Evid. §403 excludes an expert’s testimony if “its probative value is substantially outweighed by the danger of unfair prejudice, confusion of issues, misleading the jury, or needless presentation of cumulative evidence.” Expert testimony carries risks of violating Rule 403 because it can be powerful and misleading, and thus difficult to evaluate. Daubert, 509 U.S. at 595. Due to this risk, it is important for this Court to carefully weigh the probative value of CST Sita’s proposed testimony under Rule §403. Id. at 595. This raises an important question of admissibility, not just one of weight. Here the government is seeking to introduce expert testimony that uses the cell site data to place Montalvo near certain locations such as her home, the homes of others, and various locations in and around St. Cloud, FL. The State has put forth draft reports with precise pie wedges shapes 7drawn in a compelling manner to try to prove Montalvo was in certain key locations at specific times. However, the actual methodology (or lack thereof) behind these plotted maps does not support that conclusion. There is a serious danger of unfair prejudice that far outweighs their probative value and they should be excluded. CONCLUSION For all the reasons set forth in this motion, Mr. Otero-Rivera, respectfully requests that this Court exclude any and all testimony of CST Sita regarding the cellular analysis conducted in this matter, as well as the associated maps and reports of CST Sita. Mr. Otero-Rivera further request a hearing on this matter so that he may have the opportunity to demonstrate to the Court that CST Sita’s conclusions are not reliable and therefore should not be admissible. CERTIFICATE OF SERVICE I] HEREBY CERTIFY that a true and correct copy of the foregoing has been E-filed thru the E-file Portal System to the State Attorney’s Office, rwilliams@saoS5.org and JMcManus@saoS.org; on this 16" day of May, 2020. oN “ ) om VA a ce [Aa doh kc - U ss Migdalia Perez, Esq., FBN: 696307 517 Bryan Street Kissimmee, FL 34741 407.530.4920 Office 407.540.9351 Fax mperez@perezlasurelaw.com By: KIMBERLY A. LaSURE Florida Bar No. 883751517 Bryan Street Kissimmee, FL 34741 407.530.4920 Office 407.540.9351 Fax Klasure@perezlasurelaw.com