'Back then, come here with long hair, also cannot. The officers will tell you to get it cut. We also had to wear long-sleeved shirts,' he recalled in Hokkien.
He was then 22. He moved on from drug abuse to heroin trafficking and served a lengthy spell in prison before he was released three months ago.
Because he had consumed drugs before, he was again put on drug supervision, and he has to report regularly to the Central Narcotics Bureau (CNB) for urine tests.
This time round, the 47-year- old unemployed man does not mind it as much. Not just because he knows he is clean but because the process is much faster. 'Now, the test results are out in 10 minutes and I can leave,' he said.
The process has improved over the years, cutting down on the waiting time for test results.
Before 1988, there were no instant urine test machines, which take only 15 minutes to detect drugs in a urine sample. The CNB had to release suspects on bail after they submitted their urine samples as it took a fortnight for the then Department of Scientific Services to come back with the results. This meant that abusers could run away or disappear.
A CNB spokesman said: 'The machines drastically cut down the number of drug abusers on the run.'
While the new machines proved to be a boon, officers found themselves with another problem.
When a suspect is hauled in, he has to provide three bottles of urine samples. One bottle is used for immediate testing, and the others are sent to the Health Sciences Authority's (HSA's) laboratories for a conclusive test.
Before 2004, two bottles of urine were needed to run tests on each drug type. Officers often ended up waiting up to six hours for an abuser to fill as many as eight bottles.
Depending on the drug tested for, it takes a week to a month for lab results to be known. Meanwhile, the suspect may be sent to a drug rehabilitation centre.
From 2004, the HSA needed just two bottles to test for any number of drug types. 'This also helps us with people who refuse to pee. Now, we just need them to pee once,' said the officer.
The bureau has recently completed trials on using a suspect's hair to test for drugs. Compared to urine tests, hair tests can turn up evidence of drug use for a longer period after they were consumed.
TEH JOO LIN