‘I’ll never know why,’ British man says of participating in 2017 murder

Andrew Warren, who has pleaded guilty to Trenton Cornell-Duranleau’s murder, was testifying against Wyndham Lathem, a former Northwestern University professor.

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Andrew Warren arrives at a police station as he is escorted by Chicago police, on Aug. 18, 2017, in Chicago.

Andrew Warren arrives at a police station as he is escorted by Chicago police, on Aug. 18, 2017, in Chicago.

Jim Young | AP Photos

Andrew Warren said when he and Wyndham Lathem met online, they were both suicidal and had planned to have themselves killed in Australia.

However, when that deadly scheme didn’t work out, they discussed marriage and killing each other instead, Warren testified Wednesday.

That plan didn’t pan out either. But the two did end up murdering someone: Lathem’s boyfriend, 26-year-old Trenton Cornell-Duranleau, Warren told Cook County jurors.

Cornell-Duranleau “started screaming” when he and Lathem, then a Northwestern University professor, repeatedly stabbed the sleeping man in Lathem’s River North condo, Warren said.

Warren also said that he was supposed to film the 2017 murder but couldn’t muster up the courage to do so.

“I couldn’t do it,” Warren, 61, said in a deadpan voice.

When Assistant’s State’s Attorney Yolanda Lippert asked why he participated in the murder by grabbing a knife from the kitchen, Warren said, “I don’t know why. I’ll never know why.”

Warren said he pleaded guilty to Cornell-Duranleau’s murder in 2019 as part of an agreement with prosecutors: They would recommend he be sentenced to 45 years in prison in exchange for his testimony against Lathem, 47.

A tired-looking Warren, who wore a bright yellow jumpsuit in court Wednesday, said there is a possibility that he would be returned to the United Kingdom at some point to serve his sentence, but added that he wasn’t assured that would happen.

Lathem’s attorneys have argued that it was Warren who killed Cornell-Duranleau in a jealous rage after Lathem broke up with him following a brief romance that lacked a “spark.”

But Warren said he was never jealous of Cornell-Duranleau’s relationship with Lathem.

Warren, a former Oxford University financial officer, was a “gold digger,” solely attracted to Lathem for his money and social status, defense attorney Barry Sheppard suggested during cross examination.

While Warren agreed his financial situation was “horrible” when he met Lathem online, he said he wasn’t drawn to Lathem because of his bank account.

Warren said he was depressed and suicidal when he connected with Lathem virtually. Lathem was also considering suicide at the time because he hadn’t gotten a job he wanted, Warren said.

The pair decided to go to Australia after a man they met on a website offered to kill them both.

But the Australian man booked a cruise, failing to carry out his end of the deal. So Lathem got Warren a plane ticket to Chicago instead, Warren said.

Neither man had discussed murdering Cornell-Duranleau then, Warren said. But Lathem and Warren did discuss marriage and killing each other, with Lathem offering to buy rings, Warren said.

Trenton Cornell, who was found dead in River North condo July 27, 2017.

Trenton Cornell-Duranleau


The plot to kill Cornell-Duranleau — Lathem’s idea — didn’t come up until the night he was stabbed 78 times, Warren said.

Days before, Lathem and Warren took crystal meth in a hotel room after Lathem picked Warren up at the airport, Warren said. They then drove to St. Louis to allegedly buy a gun so Warren could shoot Lathem. Lathem “was going to cut me open ... and fatally wound me,” Warren said of the men’s initial plan.

But they couldn’t buy a weapon because they couldn’t show proof of residency, Warren said.

It was during that drive back to Chicago that Lathem suggested murdering another person, Warren said.

Later that night, Warren, who was in his hotel room, said he got a text from Lathem asking him to come over. Lathem also mentioned that he planned to kill “Trent,” Warren said.

“I thought it was his roommate,” Warren said. “I said, ‘I don’t want to do this, I don’t want to be a part of it.’”

Wynham Lathem arrest photo

Wynham Lathem arrest photo

AP Photos

Still, Warren went to Lathem’s condo. When Warren got there, he said Lathem suggested they go into the bathroom to avoid rousing Cornell-Duranleau.

Lathem injected himself with crystal meth in the bathroom, showed Warren the serrated drywall knife he planned to use on Cornell-Duranleau and gave Warren his cellphone, Warren said.

Then, “We both got undressed, in case there was blood everywhere,” Warren said.

Warren said he proceeded to follow Lathem to the bedroom, where he saw a napping Cornell-Duranleau.

Lathem first stabbed Cornell-Duranleau, Warren said.

Warren said he also stabbed the screaming Cornell-Duranleau twice in the lower abdomen and struck him in the head with a side table lamp.

He said he tried to silence Cornell-Duranleau by putting his hand over his mouth, until he was either bitten by Cornell-Duranleau or was stabbed by Lathem’s knife.

Bleeding, Warren said he moved away from the bed and Cornell-Duranleau eventually fell to the floor.

Afterward, Warren and Lathem showered, left Lathem’s condo and went to the hotel room across the street that Lathem had booked for Warren, Warren said.

The men then fled the city, leading to a national manhunt before they turned themselves in.

Cornell-Duranleau’s body was discovered in Lathem’s condo by Chicago police on July 27, 2017.

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