Hennepin County crime lab halts testing after DNA contamination detected

At least 75 DNA samples may have been impacted by a reported contamination at the Hennepin County Sheriff's Office crime lab.

What we know

The sheriff's office says DNA contamination was found in casework from an unknown source in September.

Due to the discovery, the sheriff's office says it halted all DNA analysis to determine the origin and impact of the contamination.

Right now, the sheriff's office says the contamination was likely from "an external product we use in the DNA testing process."

The impact

The Hennepin County Sheriff's Office says, so far, out of 50,000 samples, they've identified 75 samples that may have been impacted by the contamination. But work is still ongoing to identify affected samples.

"It is important to note that because the contamination is due to an unknown DNA profile, no criminal charges or convictions could have resulted from this contamination," a sheriff's spokesperson said. "Our number one priority remains the integrity of our casework and ensuring the accuracy of DNA analysis. We will continue to work with our criminal justice partners throughout this process, and we will provide additional information as it becomes available.

Reaction

In a statement, the Hennepin County Attorney's Office wrote:

"We are taking this issue extremely seriously. The HCSO Crime Lab alerted our office to this problem on Sept. 26, 2024, and we immediately began notifying defense counsel and initiated our own internal review process.

"The most recent update provided to our office from the HCSO Crime Lab indicates that approximately 75 samples are potentially impacted. We are working continuously to identify any affected cases and are collaborating closely with the Crime Lab. We are committed to transparency and to ensuring integrity in all of our work."