Marian Tom Parlov, 47, was serving a three month weekend detention sentence at Symonston Correctional Centre for driving offences when he was caught with the drug in October last year.

The court heard guards discovered the offence after they smelt burning and heard coughing coming from a nearby cell.

They found Parlov holding a cigarette lighter and leaning over a sink coughing.

A makeshift pipe – fashioned from a coke can – still emitting smoke was located on the floor nearby.

Parlov pleaded guilty in the ACT Magistrates Court to possessing cannabis while in jail.

The defendant told Magistrate Peter Morrison that he found a small clip seal bag containing the cannabis only moments earlier after returning from a work party.

Parlov said he had “one draw and chucked my guts up”, coughing for five minutes straight.

The father-of-seven said he had nothing to do with drugs normally and the offence was “stupidity”.

Mr Morrison accepted the crime was opportunistic and noted that a small amount of cannabis was at the low end of seriousness for the charge.

Mr Morrison also noted that the sentence administration board could have made Parlov serve the remainder of his sentence in full-time custody but chose to take no action as a result of the offence.

The magistrate instead fined the disabled pensioner $300, with six months to pay the penalty.