The conviction of an American ‘‘suicide voyeur’’ who encouraged a British man and Canadian woman to take their own lives in an internet chat room has been overturned on free speech grounds.

After the Minnesota Supreme Court ruling, a lower court must now decide whether to bring fresh charges against William Melchert-Dinkel, a former male nurse who was convicted on two rare counts of assisted suicide in 2011.

William Melchert-Dinkel: conviction overturned

He was found guilty of aiding the suicide of Mark Dryborough, 32, who died in Coventry, UK, in 2005, and of Nadia Kajouji, 18, who took her own life in 2008.

In the original trial, the court was told that Mr Melchert-Dinkel, who is married with two children, posed online as a compassionate female nurse to prey on depressed individuals, but then gave them advice on how to suicide.