Murder Defendant Waives Right to Test Some Items for DNA Evidence

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Prosecutors told DC Superior Court Judge Marisa Demeo, in a May 14 hearing, they have already tested key pieces of evidence in a fatal stabbing, including three knives allegedly used in the attack. 

Warren Tyson, 54, is charged with second-degree murder while armed, carrying a dangerous weapon and enticing a child in connection to the fatal stabbing of Michael Johnson, 21, on Oct. 22, 2021, on the 4900 block of East Capitol Street, SE.  Tyson is alleged to have sent inappropriate material to a minor and that led to an altercation with Johnson. 

In addition to genetic material on the knives, prosecutors have collected DNA from reddish brown stains, a blue and white face mask and a sleeveless shirt. Prosecutors also collected DNA from the vehicle in which Tyson was arrested as well as two cell phones. 

Under the Innocence Protection Act (IPA) defendants have the right to test biological material independent of the prosecution to establish their innocence.

Tyson’s defense acknowledged that his team had performed its own tests on the knives but not everything the prosecution has tested.  While Tyson said he had just gotten the report detailing the prosecution’s results, he waived the right to analyze other evidence for DNA, which all but precludes him from doing so in the future. 

Judge Demeo set a trial date for Nov. 14. In the interim, she scheduled a motions hearing for July 26 to discuss a defense request to sever the charges against Tyson into separate trials. 

In an outstanding motion filed July 7, 2023, Tyson’s attorney, Julie Swaney argued, “A joint trial on these counts would substantially and unfairly prejudice Mr. Tyson…Furthermore, the nature of the enticement charge is extremely prejudicial and will inflame the jury to such a degree that an impartial verdict regarding the murder will not be able to be rendered.”

The prosecutor called the motion “highly dispositive.”  Judge Demeo said the issue was “ripe for a ruling.”

Earlier in the hearing, Tyson rejected a prosecution offer to plead guilty to aggravated assault while armed in return for dismissing the other charges against him.