Why would a woman kill the man she was about to be rid of?
There it was in black and white. The divorce agreement. Everything had been considered. Custody of the couple’s 2-year-old son, the financial arrangements, the property.
Only one thing remained – to sign the agreement in four days’ time. But Tianle Li wasn’t happy about divorcing her husband, Xiaoye Wang.
They’d met in the early 1990s. She’d worked hard, earned a place to study Chemistry at the University of Pennsylvania. So she’d left behind her native Beijing, China, and started a new life in America.
She’d met Xiaoye, who was from China, too. They’d made a life together. Even started calling each other by American-sounding names – Heidi and Alex.
A few years on, they married. And soon, Tianle landed a dream job in the research department of a large pharmaceutical company. Meanwhile, Xiaoye got a job as a computer-software engineer.
They set up home in Monroe, Pennsylvania, and in 2008, had a son.
There were some parts of their upbringing in China that were harder to leave behind. Like their traditions. For many Chinese people, marriage and family are the most important things in life. They give you status, respect.
But after they’d been married for 10 years, Xiaoye told Tianle he wanted a divorce. Eventually, Tianle had agreed.
She would give Xiaoye a divorce, and the couple would live together until it came through.
Now, on 10 January 2011, the details were settled. Four days and the marriage would be over.
Only, on the morning they were due to appear in court, Xiaoye didn’t feel well. He had flu-like symptoms and searing pain across his belly.
He checked himself into the University Medical Center in Princeton. His hands and feet started to feel numb, too. Then he fell into a coma.
Doctors were baffled. And Tianle seemed out of her mind with worry.
Over the next 11 days, she spent every waking hour by her soon-to-be-ex-husband’s bedside.
Then, doctors made a breakthrough. They’d found the pain in Xiaoye’s abdomen was being caused by thallium, a heavy metal that had been used to make rat poison but was now banned in the US.
Next day, 26 January, Xiaoye died of thallium poisoning.
No-one could work out how he’d ingested the tasteless and odourless poison.
Suspicion fell on Tianle. She’d ordered thallium, apparently for research purposes. She’d been making notes on Xiaoye’s symptoms too. And booked one-way tickets to China for her and her son.
It certainly didn’t seem like she had a motive for murder, though. She was well provided for in the divorce. Unless the shame of the divorce had driven her to kill?
In September 2013, Tianle stood in court charged with the murder.
But would the jury believe her?