Decked in a pink sweater, black top and jeans, she spoke confidently and eloquently and even cracked the occasional joke.
For example, when asked about the best advice her lawyer had given her, she said with a light-hearted chuckle: "Don't beat up another policewoman."
Last week, Chng, 18, was put on 18 months' probation for one count each of voluntarily causing hurt to a policewoman and committing mischief in a police car.
Her lawyer, Mr R. Thrumurgan, 42, his wife and Chng's mother agreed to be bonded a total of $5,000 to ensure her good behaviour.
Chng's brush with the law may yet turn out to be a blessing in disguise.
Mr Thrumurgan has taken her in as an administrative assistant at his law firm, Trident Law Corporation, giving her a second shot at making something of her young life.
She is now at the AG Home for teenage girls, where she will stay for the period of her probation.
Chng also has to perform 190 hours of community service and receive counselling support from a family service centre if required.
She told The New Paper yesterday that she is resolved to improve her life, which has not been smooth sailing.
Her father left the family soon after her younger brother was born 14 years ago.
She dropped out of school just before her PSLE to take care of the home as her family was financially strapped.
At 16, she began working as an odd-job labourer, earning about $900 a month.
The hours were long and she was not always paid on time, she said.
"There was an occasion when I worked as a dishwasher and I didn't get paid. I had no money and my family had no money.
"As I was walking home, I used the $2 - which was all I had - to buy a red bean bun for my younger brother. Seeing him live without electricity was just heart-wrenching. I wondered what my family did to deserve this," said Chng, who also has an older brother.
Throughout the 45-minute interview, she repeatedly thanked Mr Thrumurgan and his wife, Madam Priscilla Yip.
"No amount of words can express my gratitude to them. (He) helped me personally.
"He gave me this job and is helping me plan my future. No ordinary lawyer would do that.
"Priscilla is like a mother to me, she's my happy pill. She counsels me emotionally and keeps me in check."
She spoke proudly of her new job and said she has never felt more engaged doing work.
Hopes to study law
Looking ahead, she plans to pursue a diploma in law and take after Mr Thrumurgan by helping offenders get back on their feet, especially the young ones.
"I hope to be back in court one day. Not as an accused, but as a lawyer."
Mr Thrumurgan said Chng is very mature and a quick learner despite her age and her primary school education.
Just two months ago, she did not even know how to use a computer. Now she's able to edit videos all by herself, he said.
"I'm confident she will go far. She's adaptable and she has a lot of potential," he said.
Chng promises not to let him down.
"Life doesn't always turn out the way we intend it to, but certain choices that we make will change the course," she said.
He helps clients to 'pay it forward'
He saved a client who had been convicted of murder from the hangman's noose.
He also hired a former teenage rebel who assaulted a cop as his administrative assistant.
Lawyer R. Thrumurgan, 42, is not happy just to help his clients with their legal problems.
He and his wife, Madam Priscilla Yip, 41, who is the head of communications for Asia Pacific at Airbus Helicopters, go out of their way to help them get back on their feet - even though sometimes it might seem to be in vain.
Last week, the couple stood surety to ensure the good behaviour of a client, Carmen Chng Jiawen, 18.
Community Court Judge Mathew Joseph said this was probably the first case before him where an accused's lawyer stood surety.
Mr Thrumurgan has a history of helping his clients.
In November 2005, the Supreme Court's Legal Assistance Scheme for Capital Offences (Lasco) assigned him to take Ismil Kadar's case on a pro bono basis.
Ismil and his brother, Muhamad Kadar, had been convicted of killing Madam Tham Weng Kuen, 69, in 2005 while robbing her at home.
Mr Thrumurgan spent five years on the case, got Ismil acquitted in 2011 and then hired him as a dispatch assistant.
Unfortunately a year later, Ismil was found with 3.7g of heroin. He was jailed seven years and given six strokes of the cane.
Yesterday, Mr Thrumurgan, who has been practising law for about 16 years, and Madam Yip told The New Paper why they are so determined to help ex-offenders rebuild their lives.
"I grew up in a family where our finances were tight. We managed to get by because we had financial help from others. They took a chance with us and I wanted to make sure it was not a foolish one.
"Now I hope to pay it forward," he said.
He does so by counselling his clients, checking in on them and even hiring some of them.
On Ismil's case, he said: "I was disappointed when he turned back to crime. But I would feel more miserable if I did not help him and he turned back to drugs.
"I did whatever I could to help him. The whole firm supported him and encouraged him."
Mr Thrumurgan, who spends about 30 per cent of his time on pro bono cases, said he identifies the source of the problems in his clients' lives and advises them on how to rectify it.
As for Chng, he hopes to help her focus and improve her life.
"When I see the transformation in her life, it gives me a lot of encouragement that what we are doing is right," he said.
This article was first published on September 23, 2015.
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