Michael Marin could be seen putting something in his mouth after he was found guilty in an Arizona courtroom, NBC's Thomas Roberts reported for TODAY earlier this month.
An autopsy report confirmed Friday that Michael Marin, the former Wall Street trader who collapsed and died in court minutes after he was convicted of arson last month, committed suicide by taking cyanide.
Authorities immediately suspected that Marin, 53, killed himself June 28 in Maricopa County Superior Court in Phoenix by swallowing a homemade cyanide pill.
Marin had just been convicted of burning down his mansion in 2009 when he went into convulsions at the defendant's table. He was declared dead at the scene.
The autopsy confirmed that Marin died of cyanide poisoning, The Associated Press reported.
Marin was often described as a larger-than-life figure. He made a fortune on Wall Street, flew his own planes, held a law degree from Yale University and climbed Mount Everest.
But he had retired from finance several years ago and was no longer able to keep up with his $17,250-a-month mortgage payments, prosecutors said. So he burned down his home, on which he owed $2.3 million, and made headlines by escaping from a second-floor window in scuba gear.
After Marin's death, police found a canister of cyanide in his car, along with a note to his son saying his will was up to date and in place.
James Dearing, medical director at John C. Lincoln Medical Centers in Phoenix, said cyanide poisoning was an especially unpleasant but highly effective way to kill oneself.
"It's a very fast-acting chemical that comes in gas or crystal form," Dearing told NBC station KPNX of Phoenix. "What this chemical does is it prevents oxygen from leaving the blood and going into the cells, so the cells will die."
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