PORTLAND, Maine — Testimony wrapped up in the murder trial of a Maine man who's accused of killing a sheriff's deputy.

The trial of John Williams was delayed Monday to allow the defense the opportunity to call a final expert witness. The witness did not testify, so the judge moved the trial to closing arguments. 

Both sides agree that Williams fired the fatal shot. At issue is his state of mind. The defense contends Williams' drug use and lack of sleep left him too impaired to form the necessary intent to commit murder.

Cpl. Eugene Cole was shot when he tried to arrest Williams during a late-night encounter on April 25, 2018, in Norridgewock.

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