The Georgia Supreme Court rejected arguments from two men who said ineffective counsel led to their murder convictions, including one man who strangled his grandfather and drove the man’s truck around for two days with his body inside.

In opinions issued Monday, justices rejected appeals from Casey Ryan Collins and Justin Marquis Graves. Collins received two life sentences in the May 2013 murder of his 78-year-old grandfather, Eric Ronald Smith. Collins' girlfriend, Sarah Cook, pleaded guilty to armed robbery and aggravated assault and was sentenced to 15 years in prison. Prosecutors argued Collins killed his grandfather as he sat inside the truck parked outside the couple's Mableton home because he would not supply him with any more pain pills. An autopsy revealed Smith had been stabbed and strangled.

Collins argued that his trial attorneys did not present evidence to back up his claims that he was sexually abused by his grandfather, which led him to suffer from post-traumatic stress disorder. Collins argued that this would have led to the jury considering the lesser charge of voluntary manslaughter. The court said Collins did not present any persuasive evidence he was sexually abused or suffers from PTSD.

“… Assertions are not evidence,” the court wrote.

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Joel Bergstrom, the attorney who filed the appeal on Collins’ behalf, said if the defense had been allowed to present the sexual abuse allegation in court, it could have possibly resulted in Collins not getting a life sentence.

“Who’s to say the prosecution would not have offered a manslaughter plea if that information was proven?” he said.

Graves was convicted in the August 2015 killing of cab driver Michael Bemus, who was found dead inside his taxi cab at Allaround Suites in Marietta. In his petition, Graves argued that the state did not present sufficient evidence to support his conviction and said he was denied effective legal counsel. According to a court summary, Graves was captured on surveillance cameras getting out of the taxi following the shooting and walking to another motel where he paid for a room. Hours later, police searched Graves' motel room and found a black sweatshirt that tested positive for gunshot residue. Cops also discovered the blood stain on Graves' white T-shirt contained the DNA of the victim.

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In his appeal, Graves again argued that the cab driver was killed by an unidentified person who was a member of a gang and that his autism “prevented him from reacting in a stressing manner” after seeing Bemus killed. However, the justices wrote that Graves’ assertions ring hollow since during his motion for a new trial, he did not state he had been diagnosed with autism or indicate he told his lawyer of the alleged gang.

Alan Levine, the attorney who represented Graves in his appeal, declined to comment on the justices’ ruling.

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