ABILENE (CBSDFW.COM/AP) — Defense attorneys for a Texas prison inmate say he had a sexual relationship with the prison guard he’s accused of killing but contend the guard died of cardiac arrest.

The capital murder trial of 24-year-old Dillion Compton began Monday and his attorneys say Compton and guard Mari Johnson had a months-long relationship that concluded with an argument before her body was found in July 2016.

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Prosecutors say Compton was found with scratches on his face and his skin underneath Johnson’s fingernails.

Her body was found in a storage room at the Robertson prison unit in Abilene and prosecutors say she suffered blunt force trauma and a crushed throat.

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The defense claims the injuries were sustained when Compton attempted an “aggressive” form of CPR on her.

Compton was sentenced in 2011 for aggravated sexual assault of a child.


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