Advocate believes father’s claims that antidepressants led to him murdering his daughters

After being behind bars for nearly two decades, a convicted killer’s appeals may finally have an advocate.

MORE: 10 years later: David Crespi pens letter on murder of daughters

David Crespii is currently in the custody of the Albemarle Correctional Facility, where he is serving two life sentences for murdering his 5-year-old twin daughters, Tess and Sam.

For the past 18 years, Crespi has claimed it was his antidepressant that led him to stab both of the girls to death in their south Charlotte home on January 20, 2006. To this day, it is one of the most shocking crimes in the city’s history.

David Carmichael has a story eerily similar to Crespi.

For several years, he’s been on a crusade to warn others about the potential dangers surrounding antidepressants. He brought that information to Charlotte on Wednesday, where he was able to speak with veteran crime reporter Glenn Counts.

“On July 4, 2004, I started on the SSR antidepressant Paxil. After 3 weeks, I was psychotic, had delusions, and took my 11-year-old son’s life, Ian, and I was charged with 1st-degree murder,” he told Counts.

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One key difference that separates the Crespi and Carmichael cases is that Carmichael killed his son in Canada and was ruled insane by the court, while Crespii accepted a plea deal and was given a double life sentence.

“I was found not criminally responsible, which would be insane in the United States, went to a mental health hospital, and was there for two years,” Carmichael said.

Several people gathered at Wednesday’s event in support of the Crespi family.

Kim Crespi, his wife, forgave him almost immediately after the murders of their daughter, truly believing the cocktail of medications, which included Prozac, Ambien, and Trazodone, were the triggers behind his violent behavior.

Kim Crespi (Left); David Crespi (Right)
Kim Crespi (Left); David Crespi (Right)

“I think these dark thoughts were at a very specific time when he was adjusting to medications, and that’s a key point that doctors should be telling people,” Kim Crespi told Channel 9 in 2016, “that when you’re adjusting to medications, you can be propelled to act on your deepest, darkest nightmares, and that is what David did.”

She stood by her husband 18 years ago, and Channel 9 has been told she still does. However, she currently suffers from a severe case of Parkinson’s, which prevented her from attending Wednesday’s event.

“She needs 24-7 care now; she doesn’t have control of her neck, so she had to have somebody stand behind her and lift her head so she could continue to talk to us and make eye contact, and then she would sag back down again,” Edward Jones, a family friend, told Counts.

Before the onset of Parkinson’s, she would go visit Crespi once a week in prison, and continued efforts to have him released have not worked.

Carmichael continues to tell patients to be cautious when it comes to anti-depressants and to do their own research.

(WATCH BELOW: Crespi Story Goes Before National Audience On ABC’s 20/20)