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.

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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.

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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."

Watch the full interview with James Dearing at KPNX-TV

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Investigators believe a defendant killed himself in a Phoenix courtroom shortly after a jury found him guilty of arson, saying their theory is backed up by evidence that includes a canister labeled "cyanide" found in his vehicle more than a week after his death.

Maricopa County Sheriff Joe Arpaio said Tuesday that the family of Michael Marin, 53, received a delayed email from Marin the night after his June 28 death in court. The email led investigators to the vehicle, where they found the canister. It was turned over to the medical examiner's office unopened.

Cari Gerchick, communications director for Maricopa County, said the medical examiner's office could not immediately confirm if the canister indeed contains cyanide. Gerchick said the medical examiner's office is still determining Marin's cause and manner of death.

The email also included information about his will in case things went poorly, Arpaio said.

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After being convicted of deliberately burning down his $3.5 million Phoenix mansion, Marin collapsed in court and died.

At the time of his collapse, the judge was ordering that Marin be remanded into our custody, Capt. Brian Lee told Reuters.

"It's really sad," Arpaio said Tuesday, according to AZfamily.com.

"You have to feel bad for the family. I don't know why he did it," he added.

According to AZfamily.com, Arpaio said the poison was purchased for $68 from a California-based supplier in 2011 with Marin's personal credit card.

Video from inside the courtroom showed Marin putting his hands over his eyes after the guilty verdict was read and then covering his mouth with both hands.

Arizona man dies after arson conviction: police

Marin's mansion burned down in July 2009. "Marin couldn't pay his mortgage, so he burned down his house," the Arizona Republic newspaper quoted the prosecution as saying.

The newspaper reported that Marin barely escaped by climbing down a rope ladder from the second floor while wearing a scuba tank and diving mask to protect him from smoke inhalation.

The Associated Press and Reuters contributed to this report.

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