Police officers were on mobile patrol at Wallyford Industrial Estate when they observed a vehicle being driven by Jonathan Diggory at about 1pm on May 28.
Edinburgh Sheriff Court was told that the officers had “cause to stop the vehicle” on another matter and, while speaking to the 33-year-old driver, “the smell of cannabis was detected”.
Diggory, of Northfield, Tranent, agreed to provide the officers with a roadside saliva drug test that was said to have given a positive reading for cannabis.
He was arrested and charged with the offence and, after being taken to a local police station, he gave a further positive reading when a blood test was taken.
The court was told the blood test had found that the motorist had 16mg of the compound Delta-9-tetrahydrocannibinol per litre of blood, eight times the legal limit of 2mg.
Diggory appeared at Edinburgh Sheriff Court last Wednesday, where he pleaded guilty to the offence.
Lawyer Mary Moultrie, representing Diggory, said that her client had been diagnosed with PTSD and was using the Class B drug to medicate himself.
Ms Moultrie said that Diggory’s vehicle had been seized by police at the time of the offence and that he had also been caught driving while over the limit for the drug last year.
Sheriff John Cook told Diggory that if he offended in a similar way again then “prison will be the likely outcome”.
He banned him from driving for three years and fined him £420.