In the early 1960s, when the demand for driving licences was rising, corrupt testers and instructors banded together to cash in on t he situation.
Corrupt driving testers told instructors they would let learners pass for a fee. Some instructors would in turn charge students an inflated rate.
But this was squashed after then Corrupt Practices Investigation Bureau (CPIB) officer Ronald Naidu managed to convince a tester to work with him and provide information on such practices.
Last Saturday, Mr Naidu, a prominent crime buster, died at Tan Tock Seng Hospital following two heart attacks. He was 84.
He leaves behind his wife, three children and a granddaughter. His wake is being held at his home in Mayflower Avenue and he will be cremated tomorrow.
Mr Naidu spent 30 years fighting crime, drugs and corruption. He joined the police force in 1951 when he was 20 years old.
He also worked in the Internal Security Department, and served as an assistant director in the Central Narcotics Bureau (CNB). He retired in 1981, and became involved in consultancy work.
A CPIB spokesman told The Straits Times that it was saddened by his death.
She said: "During his... tenure in the bureau, he worked tirelessly to fight corruption and had made invaluable contributions."
A former civil servant colleague, businessman Sunny Wee, 66, said: "He was very jovial, a very warm person and a fantastic boss.
"When he noticed that someone did not look like he was in his normal mood, he would call him up, ask what the problem was and would try to solve the problem for him."
In 1972, Mr Naidu, then assistant director of CPIB, carried out an investigation into corruption among members of the national football team, who had accepted bribes to rig the results of a tournament. It led to the banning of three players and a trainer for serious misconduct.
During his stint at CNB between 1973 and 1977, he was responsible for the detention of more than 50 international drug kingpins, and played a major role in helping the bureau to curb drug abuse here.
Mr Naidu was one of the founders of the Shitoryu Karate Association of Singapore. Along with other law enforcement officers, he started the karate school in 1964.
The association's chief instructor, Mr Wong Tuang Seng, 73, said: "He encouraged people to take up karate to build up fitness and instil discipline. He was a very disciplined man."
Beyond his achievements at work, his loved ones remember him as a "100 per cent" family man.
His wife, Madam Elizabeth Wong, 77, said: "I will miss his company. We met when he was investigating my boss. I was 16 plus, and he was 24. After that, we got to know each other better and we fell in love. We got married when I was 17.
"After his retirement, he paid to go to London to study for a law degree, but he missed the family too much and he didn't want to go in the end."
His daughter, Ms Nalini, said her father was a family man who was very involved in their lives.
The businesswoman said: "He worked very long hours, but when he came home, it was absolutely 100 per cent our time.
"He was very much a mentor and I shared a lot with him. I will miss his companionship."
This article was first published on October 6, 2015.
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