During the nine months that then 18-year-old John Lau (not his real name) was under probation for his involvement in gang activities in 1998, he had tuition twice a week with probation officer Chan Wing Cheong.
But what stuck with him most through the years were not so much the tuition sessions but the times when Associate Professor Chan, a volunteer, took him for meals or cycling.
"Even when my probation ended, Mr Chan made the effort to keep in contact with me and organise outings," said Mr Lau.
"I realised there were people out there willing to help me without expecting anything in return. People are helping me - I should help myself too," said Mr Lau, now 34.
He credits the efforts of his probation officer for helping him to go from being a school dropout to earning three master's degrees - and working on a fourth.
Mr Lau is just one of the many people that Prof Chan, 49, an associate law professor at the National University of Singapore (NUS), has helped in his 21 years as a volunteer.
In October, he was recognised for his efforts with the President's Special Recognition Award at this year's President's Volunteerism and Philanthropy Awards.
Prof Chan became interested in volunteering when he was posted to the Singapore Armed Forces Counselling Centre in 1985 during national service.
"I was aware at that time of issues that soldiers faced. That got me interested in volunteering and seeing how I can be of help," said Prof Chan, who also learnt basic counselling skills during this time.
The youngest of four children of a businessman and a housewife, he decided to study law as he had always found the subject interesting.
He started his volunteering journey proper in 1993, when he returned home after completing his master's in law at Cornell University in the United States. As a young and new lecturer at the NUS Faculty of Law, he signed up to be a voluntary probation officer (VPO) for juvenile offenders.
"I started out my academic career by teaching criminal law and I knew how important it was to give a second chance to those who run afoul of the law - especially juvenile offenders who have a whole life ahead of them," he said.
Rehabilitation and education for juvenile offenders is something that Prof Chan, who lectures on family and criminal law at NUS, firmly believes in.
"The cases I take tend to be (those involving) students. It's important that they stay in school for as long as possible to achieve whatever qualifications they can," said Prof Chan. "If they make improvements in their school work, it's a direct kind of achievement they can see. Once they achieve that - that they're no longer failing - you've ignited that drive in them to succeed."
Being a VPO requires more than just policing and mentoring one's charges, said Prof Chan.
"There's also a positive side of supporting and encouraging the probationer. If they have problems, then at least they know there's someone who can discuss and help them," he said.
"I can't remember exactly how many cases I've supervised. But my guess is that I have come across at least 50 boys directly."
As a VPO, he was putting in an average of four to five hours per week into volunteer work.
"I felt that he was over-stretching himself during that period," said his wife, Mrs Wendy Chan.
"He was not only supervising probationers, but also volunteering at the Boys' Hostel and chairing the VPO Committee. But I encouraged him and he still tried to spend time with the family on weekends," said the 42-year-old housewife. The couple have two sons aged 10 and 13.
At the Boys' Hostel, he would give tuition as well as hold discussions, in small groups of five to six people, with those under probation.
In 1999, he was awarded the then Ministry of Community Development's Outstanding Volunteer Award for his work as a gazetted VPO, who has the same legal responsibilities as a full-time probation officer.
Today, Prof Chan still dedicates about two hours a week to social causes, but has shifted his focus to the elderly.
His second term at the Tribunal for the Maintenance of Parents, which he has been involved in since 2008, ended this year.
He now sits on the Adult Protection Team, which deals with suspected cases of elder abuse.
"I can affect more people, and be more impactful, by sitting on such committees and recommending policies and changes," he said. But he misses working with youth.
"I miss their sense of humour - often making fun of me for not knowing what they are talking about - and energy, which sometimes leads them into trouble."
This article was first published on Dec 1, 2014.
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