Public Defender Grills D.A. Expert on Cell Phone Mapping in Murder Trial

By Fiona Deane-Grundman

OAKLAND – Assistant Public Defender Lindsay Horstman grilled District Attorney Inspector Jason Hawks about his neutrality and the relevance of his information about cell phone mapping, here in the Alameda County Superior Court trial surrounding the 2019 shooting death of Charles Billings in East Oakland.

Under presiding Judge Leo Dorado, Horstman, who was defending Damone Hayes in this ongoing trial, asked Hawks whether the part of his job which involves preparing district attorneys for trial qualifies him as “not a neutral party.”

He responded, “I’m employed by the District Attorney’s Office, but I don’t get paid more for rendering a good opinion. I get paid hourly.”

The defense attorney pressed him on his credentials, to which he claimed, “I’ve looked at hundreds of sets of phone records. Some were mapped, some were not.”

Hawks was adamant about the fact that cell phone records “either show something or they don’t,” so the prosecution’s theory of the case doesn’t affect his interpretation of the records.

He said he looks for two things, “the date and time of the alleged incident.” He claimed that he looks at the records in their totality first, “as subjectively as possible.”

Hawks explained his process of mapping the location of cellular devices respective to the location of cellular towers, to pinpoint where the users may have been located near or at the scene of a crime.

After being qualified as an expert witness, Hawks confirmed that he had inspected the records of two phone numbers, one with a 510 area code and one with a 650 area code, surrounding the events of July 26, 2019, in which a 45-year old man was shot and killed on the 10000 block of Bancroft Avenue at about 3 am.

Referring to the calls between the two numbers as “transactions,” Hawks confirmed and described each transaction as slides appeared in the virtual courtroom. He concluded that the devices “both used towers in East Oakland in the same area of East Oakland, but not always together.” He also mentioned a break in the records at around 2:37 am, ending at around 3:16 am.

When asked if the two phones could have been in the area of the homicide in Bancroft at around 2:50 am, July 26, 2019, the Hawks responded, “I can certainly say they could have been in the area at 2:37 am. There’s no specific data for 2:50 am, but there’s no data that excludes them at 2:50.”

He stated that there is a possibility that the phones could have been in the area where the victim’s van was found on Mono Avenue in San Leandro because “both phones are used in this tower on Miramar, and it’s very close to the Mono Ave address.”

After Hawks completed the presentation of his slideshow, the defense began a line of questioning that suggested that he did not map every single call between the two phones, which he did not deny.

He also conceded that he cross-referenced between a program called CellHawk and Google to identify the specific locations of each cell phone tower, and that he did not physically go to any of the towers.

Horstman pursued the possibility that because “things affect how strong a tower can be, like line of sight, topography, and bodies of water,” the radio frequencies Hawks analyzed may have been inaccurate.

He agreed that there would be no way “to go back to T-Mobile” and get a list of down towers,” and any other factors that may have disrupted the signals. He also admitted that all of the maps in the exhibit do not reveal “the total coverage range” of each tower, as Horstman phrased.

When Horstman suggested that Hawks could not tell based upon the maps he had created whether or not a cell phone was at or near a particular location, Hawks responded, “I can only tell you directionally the cell site activation used during transaction with a network.”

The defense countered that based upon the maps that he provided, Hawks could not tell the court whether the people who were using either telephone number were at or near the Oakland Coliseum location on July 25 or July 26, 2019. Hawks was not able to refute this point.

The defense concluded with the question, “Based upon all your work and all these maps and all the investigation you provided us, you can’t tell us whether or not the users of either of the phone numbers I just listed were at or near 10100 Bancroft Avenue on July 25 or July 26 2019?”

Hawks had no choice but to agree that he could not tell the court whether they were “at or near” the said location at that time. He stated that due to the given information, he would go there to look for them if he was attempting to catch the perpetrators, but he “couldn’t guarantee that they would be there.”

The trial resumes this week.
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About The Author

The Vanguard Court Watch operates in Yolo, Sacramento and Sacramento Counties with a mission to monitor and report on court cases. Anyone interested in interning at the Courthouse or volunteering to monitor cases should contact the Vanguard at info(at)davisvanguard(dot)org - please email info(at)davisvanguard(dot)org if you find inaccuracies in this report.

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