Donald Clark wasn't able to knowingly waive his Miranda rights before he confessed to a home invasion robbery that led to a murder charge in 2016, a forensic psychologist said. 

Clark was charged with the murder of Willis Sample, 77, who died from a heart attack after he and his wife were robbed while unloading groceries at their home in Cottondale.

Clark, 21 at the time, admitted to police he and another man demanded money and guns from the couple before Sample handed over $600 in cash. He said they stole money from Mrs. Sample's change purse in their bedroom before stealing their car. A state medical examiner ruled that the stress from the robbery caused Sample’s heart attack and caused his death.

Dr. John Toppins did find that Clark was mentally competent to stand trial, but the confession would have been the only evidence in the case. With it rendered inadmissible by the psychologist's conclusions that Clark "was unable to intelligently and knowingly waive his Miranda rights during interviews with law enforcement," prosecutors asked Tuscaloosa County Circuit Court Judge Brad Almond to dismiss the case.

Almond issued orders Tuesday dropping the charge and ordering Clark's release from jail.

"While not agreeing with Dr. Toppins' conclusions, the state conceded that it had no evidence to rebut Dr. Toppins' report, nor did it have a good faith belief that further evaluation of the defendant would come to a different result, given Dr. Toppins' training, education and experience," the judge wrote.

No other suspects were charged in the case.

Sample served in the National Guard, was a rural letter carrier and a lifelong farmer. He enjoyed working at his farm, spending time with his family and attending his grandchildren’s sporting events, according to his obituary.