Quote:
Originally Posted by PoorSkillz
https://www.washingtonpost.com/local...8ce_story.html
“It’s not really junk science, it’s misinterpreted science,” said forensic expert Larry Daniel of Raleigh, N.C., who has consulted and testified for the prosecution and the defense in numerous cases, including a capital murder case in Fayetteville, N.C., where police claimed the cell-tower data showed a man was at the crime scene. “It is useful and can be used. But in the hands of a novice, this is dangerous science.”
That's how I feel on that matter until actual details are provided.
If Steven's innocent, all the power to her and I hope she proves it, but I highly doubt that's the case.
Thanks to ScousePie on Reddit for this TL;dr
*Cell Tower Locating *
So today's big Zellner article in Newsweek has everybody talking about the cell phone records again.
Zellner will need that forensic expertise if she’s going to free Avery. The case has been decided. Avery’s appeals are exhausted. Only the discovery of new evidence—of the type Zellner has dug up for men she’s represented before—will reopen the case. “We have to have new evidence that could not have been obtained before that would result in no juror believing that Steven Avery committed the crime,” Zellner says. “So that’s the standard—it’s kind of a high hurdle to jump, but we can jump it with the new technology. With someone who’s innocent, you can definitely jump that hurdle.”
She also says she’ll argue Avery’s conviction should be overturned because of ineffective assistance of counsel, arguing that lawyers Dean Strang and Jerry Buting bungled Avery’s defense by not arguing that Halbach’s cellphone records show she left Avery’s property alive.
“It’s really hard to figure out how in the world did the defense not seize on this,” Zellner says. “It would have created reasonable doubt.”
“We’ve got access to documents the public doesn’t have. We’ve got all the police reports, we can see exactly what they did and did not do,” Zellner says. “And it’s a lot more about what they did not do.”
Zellner says the biggest piece of evidence she’s uncovered is the cellphone records that show Halbach left Avery’s property before she was killed—which Strang and Buting never brought up at trial. The state says Avery shot Halbach in his garage and then burned her body in the Avery family’s salvage yard. “So it’s absolutely shocking to see cellphone records that were part of the discovery that were turned over to the defense...document her route leaving the property. She goes back the same way she came, she’s 12 miles from the property on the last ping,
http://www.newsweek.com/2016/04/08/k...ry-441470.html
So SkippTopp's question in this thread has been my intial response regarding most of the recent news about cell records and pings and some of the very good efforts of fellow redditors attempts to map out the reported cell tower locations. I've seen people do some research on reddit while discussing the DNA and EDTA evidence and so here's something similar to help analyse the claims Zellner has made today which have everybody talking. What I will be covering will be how the data from the "ping" will be analysed and what that data is.
This post by u/Classic_Griswald started my searching.
MSISDN
Is a number uniquely identifying a subscription in a GSM or a UMTS mobile network. Simply put, it is the telephone number to the SIM card in a mobile/cellular phone
https://github.com/CellularPrivacy/A...ssary-of-terms
Triangulation
Just what is Cell Tower Triangulation?
In a best-case-scenario, a cell phone's signal may be picked up by three or more cell towers, enabling the "triangulation" to work. From a geometric/mathematical standpoint, if you have the distance to an item from each of three distinct points, you can compute the approximate location of that item in relation to the three reference points. This geometric calculation applies in the case of cell phones, since we know the locations of the cell towers which receive the phone's signal, and we can estimate the distance of the phone from each of those antennae towers, based upon the lag time between the towers ping sent to the phone and the answering ping back.
In many cases, there may actually be more than three cell towers receiving a phone’s signal, allowing for even greater degrees of accuracy (although the term “triangulation” isn’t really correct if you’re using more than three reference points). In densely developed, urban areas, the accuracy of cell phone pinpointing is considered to be very high because there are typically more cell towers with their signal coverage areas overlapping.
Directional Antennae
For many cell tower networks, the pinpointing accuracy may be even greater, since directional antennae may be used on the tower, and thus the direction of the cell phone’s signal might be identifiable. With the signal direction plus the distance of the phone from the cell tower, accuracy might be pretty good, even with only two towers.
However, there are many places where there are fewer cell towers available, such as in the fringes of the cities and out in the country. If you have fewer than three cell towers available, pinpointing a mobile device can become a lot less precise.
Pings
Cellular data in the form of “pings”, which is real time geo-location tracking of a cellular phone or other cellular device by activating the emergency 911 system (E911), which will then use either a network based or handset based method for locating the phone and will provide a location estimate generated via triangulation of the phone handset.
https://github.com/CellularPrivacy/A...ssary-of-terms
So now that we're familiar with some important terms let's look at some research on Cell Phone Locating in Law Enforcement.
What follows are sections of the book: Cellular Location Evidence for Legal Professionals.
By Larry E. Daniel, EnCE, DFCP, ACE, BCE, CTNS
http://www.ncids.org/Defender%20Trai...neTracking.pdf
What is important to understand about geo-location of a cellular phone or other cellular device is that the accuracy of the geo-location is dependent on a number of factors, not the least of which is the ability of the analyst to properly interpret and present the data and the methods used to present the information.
How does Cellular Data Analysis Work?
In a nutshell, cell phone location forensics involving historical call detail records generally progresses in the following way:
A phone number is identified as belonging to a person of interest. (MSISDN)
The cellular phone company for the phone number is determined.
A warrant, subpoena or an administrative request is given to the cell phone company requesting the records for the phone.
An analyst then takes those records and plots them using mapping software such as Microsoft Street and Trips, Google Earth Professional, Microsoft Map Point, Arc GIS, or PenLink.
5.The maps will then be used to further an investigation or presented during litigation and potentially in a court of law.
The second type of data used in cellular data forensics is real time tracking of a cell phone. This is a different process from analyzing historical call detail records and has a different result since real time tracking uses the Emergency 911 (E911) system. When the E911 system is used, the location of the phone is determined using various methods that will be described in detail later in this book. However, itis important to note that the E911 system is not infallible and does not always provide an accurate location of a cell phone. An additional method that is sometimes used to attempt to locate a cell phone is geo-tagging of photos where the GPS location is recorded in the metadata of the image automatically by the phone. Geo-tagging is also a function of some digital cameras.
How is Cellular Data Analysis Used?
Cell phone location analysis is also used to locate missing persons who may have their phone with them when they go missing. This type of cell phone location is normally triggered through an exigent circumstances request to the cellular carrier to begin actively “pinging” the cell phone using the E911 location system to attempt to locate the phone.
Is There an Accurate Way to Track a Cell Phone Location?
Yes, but it can only be done in real time by using the cellular system or the cellular phone’s GPS unit to track the phone. There are basically two ways to locate a phone using technology: Handset based GPS and network based triangulation.
The second way to locate a cell phone is by triangulating the phone using network based location services. What this does is calculate the position of the cell phone relative to three or more cell towers and provides that location information back to the wireless company
Here are some of the issues with the way cell tower tracking evidence is presented:
Cell phone tracking is based on an assumption that the location of the user of a cell phone can be determined merely by the location of the cell tower with which the cell phone connects when it is in use.
Expert’s reports are based upon the faulty assumption that a cell phone connects to the closest cell tower at the time a call is placed on a nearly 1 to 1 causal basis. While it is true that this is normally the case, it is not definitive enough to state that it occurs a particular percentage of the time, nor is there any way to determine this information from call detail records, if the tower connected to was in fact the closest tower to the phone at the time of the call.
The circles and sectors (pie wedges) drawn on maps to present this evidence are based on the idea that an “expert” can demonstrate the area covered by a cell phone by drawing circles or pie shapes on a map where the circles or pie shapes represent the approximate coverage area of a cell tower and that the cell phone will be in the area defined by the circle or pie shape. The idea is that the expert can determine the approximate coverage of a cell tower by comparing the distance between two cell towers, account for a theoretical overlap of tower coverage, and then draw a circle to represent the coverage area of each tower. The basis for this method is that cell towers are sectorized, meaning that a cell tower has more than one antenna, that each of the 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. However, data regarding the actual coverage area of the any tower at the time of the incident is not provided by the cellular carrier and there is no method that can be used to 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 a call simply by comparing the distance between cell towers.
Cell phones attempt to connect with the tower emitting the strongest and highest quality signal at a given moment, not the closest. 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, only that a particular tower was recorded in the call detail records as having been used at the time for the call. 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:
a.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
b.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
c.line of sight to the tower from the cellular phone itself
d.radio signal interference from other cell towers in the area
e.the make and model and condition of the particular cell phone being used
f.multi-pathing which is a function of the terrain as 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.
g. the strength and quality of signal from the towers around the cell phone
h.whether the phone is inside a building or outside at the time the call was recorded, where structural materials 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.
Is cell tower tracking evidence junk science?
If your definition of junk science is presenting evidence that is supposed to be based on some scientific method or forensically sound practice, then I think it would qualify as such.
One of the key principals of determining a method meets the Daubert standard for science is that it is generally accepted in the scientific community.
*There is no scientific community for cell phone location evidence outside of law enforcement, those who train law enforcement and some individual practitioners. *
To say it is generally accepted does not mean it is valid unless those who are accepting it has tested it and published those results in some type of peer-review journal. To date, I have seen no evidence that any government or non-government agency has ever commissioned a scientific study to determine the accuracy or efficacy of using the methods shown in this paper to determine the location of a cell phone. Members of the FBI Cellular Analysis Survey Team (CAST) have testified in courts that the FBI has used this method in hundreds of cases to locate persons, alive and dead. However, outside of this anecdotal testimony, no evidence has been presented to show the success rate, the standardization of the protocol employed, the error rates of determining a phone location based on drawing circles and pie slices on a map, the entire methodology used to locate these persons via their cell phones, or the error rates in determining that a phone used the closest towerfor a particular phone call.
http://www.ncids.org/Defender%20Trai...neTracking.pdf
Are those not some of the same complaints people have regarding the FBI's EDTA analysis in this case? Lack of Peer Review outside of Law Enforcement?
I'm only going to include the first four but there are a lot more that you should read if you are interested in this cell phone evidence as it pertains to the Avery case. What's interesting is that I first found out about Larry Daniels, the author of the above information,who you can find more about and his qualifications here: while reading an article about how appeals based on faulty interpretation of cell phone data are being granted and people are walking free as a result of evidence and warrants secured through cell network data analysis.
http://www.economist.com/news/united...ail-two-towers
Cell-data Analysis vs. Daubert Standard
What's more a judge from Chicago ruled that cell-data analysis does not meet the Supreme Court's legal test of scientific validity and this may have potentially created reasonable doubt for the defendant in the case who was later found not guilty.
"Given that multiple factors can affect the signal strength of a tower and that Special Agent Raschke’s chosen methodology has received no scrutiny outside the law enforcement community, the court concludes that the government has not demonstrated that testimony related to the granulization theory is reliable. "
http://celltowertracking.com/Daubert_Order.pdf
But it’s in the criminal defense world where the misuse of the technology has concerned experts the most. In Chicago in 2012, U.S. District Judge Joan H. Lefkow ruled that an FBI agent could not testify to the specific whereabouts of an alleged kidnapper based on his cell records because the “theory has not been subject to scientific testing or formal peer review and has not been generally accepted in the scientific community . . . [the] chosen methodology has received no scrutiny outside the law enforcement community,” Lefkow wrote. The ruling was the first by any court in the country to find that the cell-data analysis did not meet the Supreme Court’s legal test of scientific validity.
A jury then found the defendant, Antonio Evans, not guilty.
https://www.washingtonpost.com/local...8ce_story.html
