SINGAPORE - A 25-year-old man with attention deficit disorder who left the country as a teenager to study in Australia and evaded enlistment for more than six years was on Thursday (Feb 11) jailed for 1½ months.

The sentence was handed down to Brian Joseph Chow after the prosecution appealed to the High Court against his original sentence of a $4,500 fine.

Justice Chan Seng Onn told Chow that he would have been jailed three months if not for his outstanding performance during his national service (NS), which he eventually served when he voluntarily returned to Singapore in May 2013.

Chow, who is now training to be a commercial pilot, asked through his lawyer S. H. Almenoar to defer his prison term but the request was rejected and he started serving the sentence immediately.

Chow first left to study in Australia in 2005, when he was 15. His parents had decided to enrol him at Murdoch College in Perth, which had a programme to help him manage his condition.

In January 2008, he was notified to register for NS. After a letter from the school, the Ministry of Defence offered him a deferment for his foundation course - but not for his tertiary studies. Follow-up reporting orders were issued.

In March 2009, Chow applied via e-mail to defer NS for his university studies. This was rejected. Two months later, he made the same plea and was again rejected.

He returned to Singapore two months after he graduated from the University of Western Australia.

Last October, Second Solicitor-General Kwek Mean Luck had appealed for Chow to be jailed, urging the court to build on a landmark ruling in 2014 that those who default on NS for more than two years should be jailed.

The prosecutor had urged the High Court to set a sentencing benchmark of four months' jail for young men who evade NS for more than two years but are young enough to serve their duties in full.