A man who hurled a rock from a flyover on the A9 hitting a car carrying a baby has been detained for three years.

The High Court in Edinburgh heard that Asperger sufferer Paul Booth left a leisure complex in Old Gallows Road, Perth just before 6pm on December 21.

Booth, who was already on bail, walked over a bridge crossing the A9 and Booth picked up a rock and threw it onto the road below.

Lyn Bruce, 36, was driving her Toyota Land Cruiser under the bridge at about 60mph, when the rock crashed onto the bonnet and smashed the windsceen.

A 13-week old baby, who was in the car, was protected from the flying glass by a cover, Lord Bannatyne was told.

Pleading for leniency on Tuesday, Mr Renucci said a psychologist's report detailed some of Booth's problems.

The unemployed man suffers from Asperger syndrome, attention deficit and hyperactivity disorder, obsessive compulsive disorder and Tourettes.

Mr Renucci said Booth regretted what he had done. When he threw the rock, said the lawyer: "There may have been an element of bravado and his judgment was clouded by drink."

Booth had not intended any harm, the lawyer said, but realised he could have been facing a more serious charge.

At an earlier hearing, Booth of Menzies Court, Fairfield Avenue, Perth, admitted two charges of reckless conduct.

The court heard then that last August 13, Booth had an angry phone call with a girl who had stayed with him in Perth, then gone back to Dundee.

He picked up a bag containing her clothes and took it into the garden, saying he was going to set the clothes on fire.

As the bag caught fire, Booth dropped it on the ground. He and friends stood round, using the flames to light their cigarettes.

Judge Lord Bannatyne was told that an aerosol in the bag exploded, and Melissa Sangster, who was wearing denim shorts, caught the worst of the explosion.

Her friends put her under a shower and gave her first aid but she suffered burns to about 25% of her skin surface, leaving her with permanent scars to her right leg and left shoulder.

Her face and hands escaped the blast but the pregnant teenager was in hospital for three weeks.

Sending Booth to detention, Lord Bannatyne said he was taking Booth's medical difficulties into account.