How DNA and Cell Phone Evidence in Idaho Murders Complied With the Fourth Amendment

COMMENTARY Crime and Justice

How DNA and Cell Phone Evidence in Idaho Murders Complied With the Fourth Amendment

Feb 17, 2023 5 min read
COMMENTARY BY
Charles “Cully” Stimson

Senior Legal Fellow and Deputy Director, Meese Center

Cully Stimson is a widely recognized expert in national security, homeland security, crime control, drug policy, and immigration.
There is no doubt that there are no Fourth Amendment issues with respect to the CSLI or DNA evidence in this case. Milan Markovic / Getty Images

Key Takeaways

Did the police violate the Fourth Amendment rights of the man accused of slaying four college students in Idaho?

In Carpenter v. United States (2018), the United States Supreme Court raised the standard for allowing police access to SCLI.

Under the Supreme Court’s decision in California v. Greenwood (1988), the Fourth Amendment does not prohibit the warrantless search and seizure of garbage.

Did the police violate the Fourth Amendment rights of the man accused of slaying four college students in Idaho?

Much has been made of the fact that authorities relied, in part, on genetic genealogy and DNA evidence to justify the arrest warrants in this case. But the use of such technology, and the way it was likely used in this case, was lawful, as was the use of cell site location information (CSLI) used to track the movement of the suspect’s phone.

Police have released a partially redacted affidavit that offers a clearer picture of the facts of the case and the evidence supporting the alleged killer’s arrest.

DNA At the Crime Scene

The four murder victims—all students at the University of Idaho—were found in a house near the Moscow campus. Each was stabbed to death between approximately 4:00 a.m. and 4:25 a.m. on November 13, 2022. A male and female victim were found stabbed to death in a second-floor bedroom.

Two female victims were found in a single bed on the third floor. Next to one of the deceased girls was a tan leather knife sheath. Forensic examination found DNA from an unknown male on the sheath’s button snap.

Cell Site Location Evidence

Several months before the murders, on August 21, a county sheriff in Moscow stopped the suspect for a traffic infraction. He was driving a white 2015 Hyundai Elantra with Pennsylvania plates. He provided his cell phone number to the officer.

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Every cell phone receives and sends a signal to a local cell tower when the phone is turned on. As the cell phone moves, the signal transfers seamlessly from one tower to the next in the direction the phone is moving. Cell phone service providers keep records on every cell phone using its services, including all cell site location information (CSLI). This information provides a “map” of where and when the phone went while it was on.

Law enforcement applied for and was granted a search warrant for historical phone records for the alleged murderer’s phone number, The records showed the account had been opened on June 23, 2022, for a subscriber with the name of the suspect, who was listed at an address in Albrightsville, Pennsylvania. A review of the historical CSLI data revealed that, prior to the date of the murders, the phone had pinged cell towers in the area of murder scene on 12 separate occasions—always in the evening or early morning hours.

In fact, three months before the murders, on August 21st, the suspect’s phone pinged a cell tower that provided coverage to the King Road residence for over an hour, from 10:34 p.m. to 11:35 p.m.

On the night of the murders, CSLI shows the phone at or near the suspects apartment in Pullman, Washington, at 2:42 a.m. For the next five minutes, it moves south through Pullman, then stops pinging altogether—indicating the phone was then either turned off or put in airplane mode.

Two hours later, at 4:48 a.m., the phone signal returned, pinging towers near state highway 95 south of Moscow and Blaine, Idaho. The phone then travelled south to Genesee, Idaho, west to Uniontown, Idaho, and then north, arriving back at the suspect’s apartment at 5:30 a.m.

The CSLI footprint of the suspected killer’s phone is consistent with the times, dates, and routes of the white Elantra seen in video surveillance footage recovered from his neighborhood, his university, and the roads and highways between his apartment and the King Road residence.

Did the police violate the murder suspect’s Fourth Amendment rights by obtaining his CSLI information? Not at all.

In Carpenter v. United States (2018), the United States Supreme Court raised the standard for allowing police access to SCLI. Previously, the government would apply for a court order to obtain cell phone records under the Stored Communications Act (SCA). Those requests did not have to meet the “probable cause” standard needed to obtain a search warrant, because the information was considered to be in the hands of a third party. The cell phone user therefore could have no reasonable expectation of privacy over his CSLI.

Carpenter upended that practice, requiring police to seek a search warrant for any CSLI if the scope of the request is for more than seven days of data. In Idaho, the police were fully compliant. They first sought a search warrant for two days of CSLI data, centered around the time of the slayings. After reviewing those records, they then, requested and received a warrant for all CSLI from June to December.

That data paints a damning map of the whereabouts of the suspect’s phone in the months leading up to the murders, and on the night of the crimes. Prosecutors will argue that the alleged killer scoped out the murder site a dozen times, in the dark of night, prior to the quadruple homicides. They will certainly argue that based on the map of the phone’s movement on the night of the murders, the suspect left his residence after 2 a.m., drove toward Idaho, turned off the phone while he committed the murders, and then turned on the phone after the murders were over.

When overlaid with the movement of the white Elantra, the cell phone’s movement would appear to be quite persuasive.

Genetic Genealogy

What about the admissibility of that DNA evidence? On December 27, Pennsylvania law enforcement officers retrieved trash from the suspect’s family residence in Albrightsville. Under the Supreme Court’s decision in California v. Greenwood (1988), the Fourth Amendment does not prohibit the warrantless search and seizure of garbage outside of a home.

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Lab testing compared DNA found on some of the retrieved trash and the DNA obtained from the sheath found at the crime scene. The lab concluded that at least 99.9998% of the male population would be “expected to be excluded from the possibility of being the suspect’s biological father.” In plain English, that means that the trash DNA came from the father of the person who left the DNA on the sheath at the crime scene.

The affidavit is deliberately vague on how the authorities came to this conclusion, but it’s not hard to figure out what happened. No doubt, police subjected the sheath DNA to two separate tests: one to forensically identify the DNA profile for admission into court, and one to create a SNIP-based genetic profile that might enable them to connect that person’s DNA to a close relative. SNIP stands for single-nucleotide polymorphism and is, in layman’s terms, a sequence variation that allows geneticists to identify close relatives through genetic genealogy.

Police were able to tie the profiles of the suspect and his father together and, because the suspect is an only child, this was enough to establish probable cause and arrest him for the homicides. 

If the case goes to a contested trial, the government’s case will hinge not only on the CSLI, DNA, and genetic genealogy evidence described above, but also witness testimony, audio evidence, video evidence of the travels of the defendant’s white Elantra, and other evidence of the defendant’s online activities.

Like all defendants, the Moscow murder suspect is presumed innocent unless/until proven guilty beyond a reasonable doubt. But there is no doubt that there are no Fourth Amendment issues with respect to the CSLI or DNA evidence in this case.

This piece originally appeared in the Daily Wire