A MAN who drove his work’s van on a busy motorway while on drugs has been jailed for 14 months.

Graham Stewart, 36, was later caught with a knife down his boxers after his capture on Glasgow’s M77 in April this year.

Glasgow Sheriff Court heard Stewart’s Vauxhall Astra van was spotted swerving over a two-lane carriageway heading south.

Prosecutor Graham MacDonald said: “He crashed into the crash barrier in the middle of the carriageway and continued driving.”

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A 999 call was made by witnesses who thought Stewart was under the influence of drink or drugs.

The van was stopped on Peat Road in the city’s Pollok area with Stewart in the driver’s seat.

Mr MacDonald added: “Officers immediately noted him to appear drowsy with slurred speech and dilated pupils.

“He was unsteady on his feet when being moved to the police vehicle.

“He freely stated he crashed his van into the crash barrier on the M77 and it had given him a fright.”

Stewart was examined by a police doctor who determined the he was impaired while driving through drugs.

Mr MacDonald added: “The doctor noted that he was unstable walking, not following any instructions and sleeping on the desk.”

Stewart was then searched and a brown handled lock back knife and a small white bag of tablets were found in his boxer shorts.

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The tablets returned a negative result after a drugs test but Stewart was held in custody before pleading guilty today/yesterday to careless driving.

The dad-of-four also admitted driving while unfit through drink or drugs and the unlawful possession of a knife.

Stewart, who has a previous convictions for a knives and road traffic offences, was on license and bail at the time.

Brian Fitzpatrick, defending, told the court Stewart had taken Valium tablets and was unaware of the effect it would have on him.

He added: “He was driving a work’s van at the time while employed by his partner’s cleaning company.

“The knife was something he used in the course of his employment.”

Sheriff Johanna Johnston QC asked why the knife was found in his boxer shorts.

Mr Fitzpatrick replied: “When he realised he was being stopped by the police and would be searched, he tried to conceal it.”

Sheriff Johnston also banned Stewart from driving for 17 months.