June 8, 2010 -- 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.
First Alleged Victim
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.
Assisted Suicide: Unmasking Alleged Killer
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."
Identifying the Suspect
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.
Lowe said Melchert-Dinkel boasted to her about watching on a webcam as a young Englishman hanged himself.
That man was Mark Drybrough. Melchert-Dinkel has since denied that he watched Drybrough die.
Then came a breakthrough: Lowe caught a glimpse of Melchert-Dinkel on his webcam. Apparently, Melchert-Dinkel then e-mailed a photo of him with his family.
Celia Blay sent the photos, transcripts and testimony to the FBI.
"The FBI didn't even reply to me," Blay said. "We never got a reply. And this was before Nadia's death."
"Nadia" was Nadia Kajouji of Ottawa, Canada, another of Melchert-Dinkel's alleged victims.
Kajouji's family described the young woman as a beautiful, vivacious 18-year-old college freshman who slipped into a spiral of depression after a miscarriage and a painful breakup.
"These weren't people who were terminally ill that he was targeting," said Blay. "These were just you and I in bad circumstances."
Assisted Suicide: 'I Want It to Look Like an Accident'
Blay said Kajouji was a typical target. "These weren't people who were terminally ill that he was targeting," she said. "These were just you and I in bad circumstances."
Allegedly Melchert-Dinkel, posing as "Cami," made a suicide pact with Nadia.
"I've had severe depression for 12 years. ... I know what does and doesn't work so that is why I chose hanging to use," "Cami" typed in one message.
"I want it to look like an accident," Kajouji replied. "There is a bridge over the river where there is a break in the ice ..."
"If you wanted to do hanging we could've done it together online," Cami replied, "so it wouldn't have been so scary for you."
On March 9, 2008, Nadia jumped off a bridge and was found six weeks later, when the ice thawed. "Cami" had promised to kill herself the next day.
Weeks later, Celia Blay made contact with police in Melchert-Dinkel's hometown, and they listened. Police arrested Melchert-Dinkel, and he was charged April 23.
According to police, Melchert-Dinkel confessed that he had "encouraged dozens of persons to commit suicide," entered into "10 to 11 suicide pacts online with individuals all over the world" and "assisted five or less individuals in killing themselves."
Police said Melchert-Dinkel told them he did it for "the thrill of the chase."
But he was never present at a death, never met his victims and never supplied equipment or drugs. He did nothing but chat online.
"Our belief is that Mr. Melchert-Dinkel will be acquitted," said Watkins, the defense attorney.
Perhaps the defendant's best hope of acquittal is if words like these are deemed free speech:
"Attach the noose or loop to yourself then step off and hang successfully."