Reversing the conviction of an ex-nurse who relentlessly urged two people online to kill themselves, the Minnesota Supreme Court on Wednesday rejected on constitutional grounds the state's ban on encouraging and advising suicide.

The ruling still allows prosecution of people whose direct assistance causes a suicide, which could include a physical act or even use of speech. That portion of the law, the justices said, doesn't violate First Amendment free-speech protections.

The controversial case of William Melchert-Dinkel will now be sent back to Rice County District Court, where a judge will have to decide if the former nurse from Faribault intentionally assisted rather than encouraged the suicides of Mark Drybrough, 32, of England, and Nadia Kajouji, 18, of Ontario. Melchert-Dinkel posed as a young, suicidal, female nurse and tried to persuade the victims to hang themselves while he watched via webcam. He was convicted in 2011 and sentenced to a year in prison, which was stayed during the appeals process.

Rice County prosecutor Paul Beaumaster said the court's ruling came at the intersection of the principles of free speech vs. protecting the vulnerable who might be preyed upon. The U.S. Supreme Court, which could be the next stop for this case, has never considered a First Amendment challenge to a law that prohibits assisting another to commit suicide, Wednesday's ruling noted.

The ruling drew criticism from some, including state Sen. Warren Limmer, R-Maple Grove, former chairman of the state Senate's Judiciary Committee.

"It really pushes back Minnesota's tradition of protecting vulnerable people and people with medical conditions," he said. "The ruling allows a person to convince another to end it all by suicide, and that starts to make our society a little too harsh."

The case of Melchert-Dinkel, now 51, has drawn intense legal scrutiny, along with one involving a Florida-based group called the Final Exit Network and four of its members in connection with the 2007 suicide of a 57-year-old Apple Valley woman.

Robert Rivas, an attorney for Final Exit, called Wednesday's ruling a major victory for the First Amendment.

He chastised the state Court of Appeals' previous decision upholding Melchert-Dinkel's conviction as "some kind of activist judging with total disregard for the law." He said 37 states have laws against assisting suicide, and with the Minnesota ruling, only six of those states also consider advising and encouraging it to be crimes.

The Final Exit case involved four members of the group who in 2012 were charged with advising and encouraging the suicide of Doreen Dunn of Apple Valley, who left a letter saying she suffered from excruciating chronic pain. That case, which had been put on hold until Melchert-Dinkel's appeal was complete, now will be heard by the state Supreme Court.

Final Exit says it provides information to mentally competent people with chronic, incurable conditions who want to end their lives.

Dakota County Attorney Jim Backstrom said the high court's decision in the Melchert-Dinkel case "will certainly impact our prosecution of Final Exit Network." Rivas said he believes it's practically preordained how the state Supreme Court will rule in that case.

In Melchert-Dinkel's case, the court ruled 4 to 1, with Justice Alan Page dissenting. He agreed with the majority that advising and encouraging suicide were unconstitutional, but said he didn't believe the case needed to be sent back to district court. Because Melchert-Dinkel was already convicted on advising and encouraging, "the State isn't entitled to a second bite of the apple," Page wrote. "A remand will do nothing more than waste judicial resources."

Attorney: Not a 'monster'

Terry Watkins, Melchert-Dinkel's attorney, said Wednesday that there isn't any evidence his client assisted in the suicides committed in England and Canada. He said Melchert-Dinkel is relieved at the ruling and continues to regret his actions. The experience has been harrowing for his family, Watkins said.

"If he was a monster, I would have never taken this case years ago," he said.

The Minnesota Police and Peace Officers Association and the National Alliance on Mental Illness of Minnesota had filed briefs opposing Melchert-Dinkel's arguments. Dennis Flaherty, executive director of the police group, said officers, who often respond to calls about suicidal people, believe that weakening the law may make their jobs more dangerous.

But Watkins said he doesn't believe that it was the Legislature's intent that the law go beyond punishing a person who directly assists in a suicide. The constitutional question has never been answered, and the U.S. Supreme Court may want to take on the case to get all the states on the same page, he said.

University of Minnesota Prof. Michele Goodwin said the U.S. Supreme Court rarely rules in a way that could suppress an individual's right to speak.

The courts will need to continue addressing new frontiers involving online speech and the First Amendment, she said. While it may be true that the new assisted-suicide law will make prosecutions more difficult, she noted there have only been six successful cases in Minnesota.

Beaumaster, the Rice County attorney, said the ruling was thoughtful and a difficult decision. While he said he believes his position should have been upheld, he said he doesn't presume to have the ultimate answer on the complex issues addressed in the case.

"There are myriad positions where the line should be drawn," he said.

David Chanen • 612-673-4465