The family of victim Jonathan Higgins, 15, branded the sentence "disgusting" and spoke of their hate for pusher David Adams, 27.

Jonathan was among a group of goths and moshers outside Wakefield Cathedral when Adam pestered him to buy drugs.

He bought what he thought was an ecstasy tablet from Adams, but it was subutex – a powerful morphine tablet designed to wean heroin users off their addiction.

Jonathan bought two pills, took one and gave one to friend Richard Burton who was celebrating his 21st birthday on February 24 last year before the pair went drinking.

Leeds Crown Court heard Richard was violently sick but Jonathan later fell into a coma on the sofa at his home in Dent Drive, Eastmoor, Wakefield and was found dead the next morning by his mother, Fiona Phillips.

After the sentencing hearing Jonathan's sister Erica said: "I think it is disgusting, three years for somebody's life. I hate him (Adams) that's all I can say, I can't say anything about him he is disgusting."

She added: "Jonathan didn't take drugs, it was one mistake, nobody's perfect but he paid with his life."

The court heard Jonathan died after choking on his own vomit.

Jonathan was due to be interviewed for a place on an IT and Business Studies course at Wakefield College.

Neil Clark, for Adams, said his client was not aware of the consequences of selling Jonathan the drugs.

Judge Ian Dobkin jailed Adams of Langthwaite Lane, South Elmsall, for three years and three months.

He had admitted supplying a class C drug, attempting to supply a class A drug, theft and breach of an anti-social behavioural order.

Last April Adams stashed a bottle of gin in a child's pushchair at the Co-op store in Ackworth and threatened to stab store staff in the neck if they woke the infant.