A doctor was yesterday found guilty of supplying LSD to friends at a party last summer.

Michael McKenzie, 25, who was formerly a specialist in obstetrics and gynaecology at Glasgow Royal Maternity Hospital and now works in England, denied he had given the Class A drug to friends last July.

However, Sheriff Neil Douglas found him guilty at the end of the two-day trial at Paisley Sheriff Court.

He deferred sentence for three weeks and called for background reports and a community service assessment.

The court was told how Mr Alexander Robertson, an off-duty police constable, suffered hallucinations after he took a small ''tab'' of the drug at the party.

He was suspended from duty and later resigned from the force.

The former policeman told the court he had been ''given the acid'' by McKenzie while both were at the party with friends.

McKenzie, 25, of Hawkhead Road, Paisley, denied five charges of supplying the Class A drug to others. At the close of the Crown case, two of the charges against him were dropped.

The former policeman, who resigned from Strathclyde Police last week, said his experience had been nightmarish. After he was given the drug, he left the house and wandered the streets.

Eventually, he stumbled into K Division's Mill Street headquarters in Paisley to seek help.

He said he had begun to hear voices and howling in his head. He said everyone ''looked like zombies''.

Mr Robertson, 24, of Green Road, Foxbar, Paisley, said he had gone to the party last July, knowing there would be drugs available.

After he was given the LSD by McKenzie and began to suffer a bad reaction, he went out looking for help.

He left and returned to the party where his hallucinations became so bad that he dialled 999 and reported that he had overdosed.

Police went to the house at Alexandra Gate, Paisley, and he was taken to hospital for treatment.

He told the court: ''This has devastated my life and career.''

The court was told that party-goers had shared several cannabis ''joints'' and cans of beer before police arrived.

Giving evidence, McKenzie, a graduate of Glasgow University, claimed had had taken controlled substances only once in his life - in 1996 when he went on holiday to Amsterdam where he smoked cannabis three or four times in licensed ''coffee shops''.

He denied he had ever seen any of his friends involved in drug-taking and refused to accept that any drugs - especially LSD - had been in circulation on the night of the party.

The court had earlier heard that several cannabis ''joints'' had been smoked.

One of the McKenzie's friends, Barry McCready, of Marjory Drive, Paisley, said Mr Robertson had suddenly ''begun to act in an erratic manner''.

He told police McKenzie had given him a packet of Rizla cigarette papers which contained what he believed to be ''six to eight tabs of acid'' and asked him to ''hold on to them and keep them safe''.

Mr Michael Carnohan, 25, a laboratory manager, of Polson's Crescent, Paisley, who shared the flat in which the party took place, agreed that by the time police arrived Mr Robertson was ''in quite a state''.

He told the court: ''He said he thought he was a tree. I was quite worried.''

Finding McKenzie guilty, the sheriff said although that it had been difficult to distinguish fact from fantasy as Mr Robertson recalled events, due to ''the terrible consequences of what had happened to him'', he had no reason to disbelieve his account.

The sheriff said it was clear cannabis had been smoked at the party, yet, according to McKenzie, he had been unaware of that.

The sheriff added: ''His version cannot stand against that of the others and is therefore not acceptable.''