Dequan Lynn Williams, 28, died after a police shooting at his home on Kelly Drive in York, Pennsylvania, on October 17, 2015. His mother had called police saying he had schizophrenia, was off his medication, and was behaving erratically. Officers Stephen Aderhold and Jeremy Mayer found Williams outside pacing with a knife. Repeated commands to drop the weapon did not produce compliance, and a taser deployed by Officer Mayer was ineffective.

According to the official report, Williams allegedly threw the knife at one officer and then charged the other. Both officers fired their service weapons; Williams was struck, taken to York Hospital, and pronounced dead. The Pennsylvania State Police investigated and forwarded their findings to the York County District Attorney’s Office. In March 2016 the district attorney concluded the shooting was justified and no charges were filed against either officer.

Are there details about the moments before officers arrived or about Williams’s treatment history that could help clarify what happened?