A 77-year-old New Canaan man who told police he accidentally shot and killed his wife is now charged with her murder.

Albert Kokoth, who looked frail and confused in Stamford court for his arraignment Tuesday, has been in custody on lesser charges since the incident on May 6.

He needed help walking into the courtroom and appeared to be repeating "I'm not the guy" as he did so.

Margaret Kokoth, 75, was shot to death inside the couple's home on Down River Road in New Canaan. They had been married more than 46 years at the time.

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Kokoth called his daughter, then 911, telling both he was showing his wife his shotgun when it went off by mistake.

Assistant State's Attorney Dan Cummings said forensic evidence shows the shooting was an intentional act.

“The New Canaan police have evidence the defendant fired the shotgun, emptied the cartridges, then reloaded and fired again,” he said.

Court documents show Margaret Kokoth died from two separate shots – one to her head, the other to her torso. Police also found a slug in the wall and fragments in the ceiling, concluding this was no accident.

A neighbor said he heard two distinct shots, 15 minutes apart.

Defense Attorney Mark Sherman told News 12 that his client's state of mind will be part of his defense.

“I can’t get into the specifics about any diagnosis, but I can tell you mental health is going to be an issue in this case,” he said. “Right now, everyone’s just trying to process this and move forward in the most compassionate way possible.”

Kokoth's arrest warrant says one of his sons-in-law told police that Kokoth's daughter had concerns about her dad for the past few months due to dementia. She even told her husband, "If they don't do something, they're gonna find her mother shot dead."

The warrant includes a report from an officer on scene who heard Kokoth utter to a daughter, "Now they have something exciting to post in the NewCanaanite” – a local publication.

Another officer overheard Kokoth tell her, "This is some Mother's Day gift."

Sherman has asked that his client be given a wheelchair for future court dates. He said Kokoth has been having mobility issues unrelated to anything with this case.