A drug offender, who did not want to go for compulsory urine tests, submitted forged medical certificates (MCs) for outpatient sick leave.
Sahlan Moati, who is jobless, used three forged MCs as genuine and presented them on Jan 29, 2016, to his supervision officer from the Central Narcotics Bureau (CNB).
Sahlan, 37, was sentenced yesterday to eight years and four months' jail with five strokes of the cane.
He pleaded guilty to four drug-related offences and one count of forgery.
Eight other charges for similar offences were considered during sentencing.
For his earlier drug-related offences, he was placed under compulsory supervision for two years on Oct 20, 2015.
He had to go for urine tests at Bedok Police Divisional Headquarters every Monday and Friday until Oct 19, 2017.
But he returned to abusing drugs and decided to skip the tests.
A woman identified as Nursusilla Kassim, 26, had provided him with the forged MCs, purportedly from Tan Tock Seng Hospital, and he presented them to his supervision officer.
Court documents did not reveal how Nursusilla, who was sentenced to 10 weeks' jail in March 2017, obtained the documents.
The forged MCs were for Jan 15, 22 and 25, 2016, said Deputy Public Prosecutor Jane Lim.
Sahlan was arrested on Dec 20 that year and was out on bail when he absconded.
At around 6pm on Feb 26 last year, CNB officers arrested his girlfriend, Norlela Rahmat, 34, who had packets containing a powdery substance in her possession.
Through her, the officers caught Sahlan about five hours later. He provided two bottles of his urine sample after he was taken to the CNB Enforcement Office. They were later found to contain traces of methamphetamine.
The court heard that the packets found in Norlela's possession contained 3.44g of diamorphine, or pure heroin.
The DPP said: "Investigations revealed that the accused admitted to jointly trafficking drugs with Norlela by handling, packing and selling drugs together with her."
Court documents did not reveal the outcome of Norlela's case.
For being in possession of the drug for the purpose of trafficking, Sahlan could have been sentenced to up to 20 years' jail and up to 15 strokes of the cane.
Those convicted of trafficking more than 15g of heroin may face the death penalty.