William Melchert-Dinkel, a family man from a small town in Minnesota, is a career nurse and a regular churchgoer. He's also the first person ever to be charged with assisting suicide over the Internet.
Prosecutors claim that Melchert-Dinkel, 47, coaxed two people he met in online chat rooms into killing themselves.
Melchert-Dinkel's attorney, Terry Watkins, denied the charges and said that he believed his client would be acquitted.
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"The crux of the case is going to be whether the evidence ... meets the elements of the crime as defined by the Minnesota statute," said Watkins.
According to prosecutors, Melchert-Dinkel met two alleged victims in online chat rooms where he posed as a concerned female nurse, using such pseudonyms as "Li Dao" or "Cami."
Melchert-Dinkel allegedly struck suicide pacts with his correspondents, who then followed through.
One of the people Melchert-Dinkel chatted with was 32-year-old Mark Drybrough of Coventry, England. Drybrough's mother, Elaine Drybrough, said her son suffered from depression.
She blames Melchert-Dinkel for her son's 2005 death.
"I feel that he killed Mark," said Drybrough, describing what she said was a suicide pact the defendant had made with her son. "He said he was a nurse in his 20s. He said he was a woman, he said he had bipolar disorder for 10 years and nothing had worked."
Mark Drybrough hanged himself in his apartment. His sister, who found the body, said she also found e-mails from Melchert-Dinkel on Drybrough's computer.
"You can easily hang from a door ..." Melchert-Dinkel allegedly wrote in one message.
"I felt somebody had killed my son," Elaine Drybrough said. "Somebody was out there, virtually a serial killer, still doing it over and over again and nobody was stopping him."
Unbeknownst to Melchert-Dinkel, however, he was being watched. Not by police or federal authorities but by a 64-year-old Englishwoman, Celia Blay.
Blay, a retired teacher and amateur local historian, browsed chat rooms on an old computer in her attic. She first learned of Melchert-Dinkel in 2006 when she met a young South American woman online.
The young woman abruptly told Blay about a suicide pact she had made online with another woman, a young female nurse.
"I couldn't dissuade her because she said, 'I didn't want to let the other girl down,'" Blay told ABC.
Blay said she unmasked Melchert-Dinkel by meticulously monitoring traffic in suicide chat rooms.
With the help of a friend, Blay uncovered all his aliases, where he worked. She discovered his name.
"By that time we had about 50 cases that we knew of, that he'd been in touch with suicidal people," said Blay. "We knew his age, his address, we knew everything about him, his family, what he did at church, you know."
Blay said Melchert-Dinkel communicated in a specific way that allowed her to recognize him.
"His spelling is dreadful," Blay said. "He uses the word 'hon,' and he says, 'I understand.' His language is very distinctive."
Blay took her findings to the British police, but she said they did not take her seriously.
"The parting shot as I left the police station was, 'If it bothers you, look the other way,'" Blay said.
But Blay continued to track Melchert-Dinkel with the help of her friend, Kat Lowe, who began corresponding with him over e-mail.