Battle over ballistics evidence in 2 alleged Phoenix serial killers’ trials

PHOENIX (AZFamily) — Death penalty trials for two accused serial killers in the Valley are rapidly approaching. Their names are Aaron Saucedo and Cleophus Cooksey.

Both men are accused of killing nine people in two separate cases.

Now, their defense teams are trying to get the ballistics evidence thrown out, citing a controversial report from 2016 that brings science into question.

Saucedo and Cooksey are considered two of the most prolific reported killers in the Valley in the last decade.

In Cooksey’s case, the killings spanned three weeks in 2017. The victims included his own mother and stepfather.

Saucedo’s alleged reign of terror went from 2015 to 2016 in the Maryvale neighborhood of Phoenix.

“Ballistic identification is very important in a firearms case,” said defense attorney Jason Lamm. Lamm is a prominent Arizona defense attorney who is unaffiliated with these cases but well-versed in the issue at hand.

Ballistic identification is when experts look at things like bullets and shell casings to determine which gun they were fired from. If bullets and the gun are linked to the suspect in the case, that becomes a huge piece of evidence for the prosecution.

But here’s the catch.

Lamm explained that in 2016, the Presidential Commission on Applied Sciences and Technology (PCAST) issued a report that questioned the reliability of ballistic identification because of variations and subjective components in the process.

He said the defense will lean on the subjectivity and variability of this kind of science to try and sway the judge it should not be allowed at all in death penalty trials.

“If the ballistics were to be thrown out, it would be a blow to the prosecution and a win for the defense, particularly in a capital case like this,” said Lamm.

But he said history in Arizona and the nation shows that judges typically allow ballistic evidence in court. Lamm believes that with these two defendants, the judge will likely determine the prosecution and defense should have their ballistics experts be part of the trial, and it’s on them to convince the jury how they should view this kind of evidence.

Both sides will present several days of oral arguments to the judge in mid-November, and she’ll decide from there whether they get an evidentiary hearing on this.

For now, Aaron Saucedo’s trial is set for February 2025, and Cleophus Cooksey’s trial is set for April 2025. However, due to the complexity of the cases, they could be pushed back.

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