SINGAPORE - The younger son of a prominent lawyer admitted on Friday (Oct 6) that he had defaulted on his national service obligations for about six years.

The court heard that Isaac Tan Yang En, now 25, whose father is Senior Counsel Tan Chee Meng, had remained outside Singapore without a valid exit permit for nine years - between Aug 15, 2006, and Aug 5, 2015.

His six-year period of default started from Mar 16, 2009 - when he turned 16 1/2 years old and was required to register for NS.

Isaac Tan, who is now serving his NS and will complete it later this month, pleaded guilty to one count of remaining outside Singapore without a valid exit permit.

A second charge for a similar offence and one count of failing to comply with a Further Reporting Order to report for NS registration, pre-enlistment documentation and medical screening will be taken into consideration during sentencing.

Deputy Public Prosecutor Tan Zhongshan told the court that Isaac Tan is a Singapore citizen by birth.

On Dec 1, 2000, he migrated to Canada with his mother, older sister and older brother Jonathan Tan Huai En. However, SC Tan remained in Singapore because of the lack of employment opportunities overseas.

DPP Tan said: "The family decided to migrate to Canada as the accused and Jonathan were unable to cope with the Singapore education system's policy of studying a compulsory mother tongue language. The accused also suffered from atopic dermatitis, exacerbated by the hot and humid weather in Singapore."

Atopic dermatitis is a type of eczema which often appears as a red, itchy rash.

Isaac Tan received his Canadian citizenship in early 2005. The court heard that on Sept 8, 2009, SC Tan's lawyers wrote to the Central Manpower Base (CMPB), requesting that Isaac Tan's NS be deferred until he turned 21, when he intended to renounce his Singapore citizenship. The CMPB replied later that month, rejecting the request.

DPP Tan said: "CMPB also stated... that the accused had been remaining outside Singapore without a valid exit permit, and the accused should return to Singapore to resolve his NS offences as soon as possible in order not to prolong his default period."

On May 26, 2011, CMPB again wrote to SC Tan, rejecting a request that Isaac Tan be allowed to renounce his Singapore citizenship without serving NS.

Isaac Tan returned to Singapore on Aug 6, 2015, and enlisted into full-time NS about two months later.

DPP Tan said Isaac Tan had been aware of his NS obligations from a young age and urged District Judge Marvin Bay to sentence him to at least three months' jail.

In mitigation, Isaac Tan's lawyer, Ms Josephine Choo, told Judge Bay that the sole purpose of her client returning to Singapore was to fulfil his NS obligations.

She also said that her client has been suffering from atopic dermatitis since birth and still needs to go for regular follow-up treatments.

Ms Choo, who pleaded for a five-week jail term, added: "Isaac's (skin condition) appears to have worsened since he started serving NS and the CMPB has deemed his condition severe enough to warrant a downgrading of his fitness status to PES E. Consequently, Isaac is being assigned only clerical work."

PES refers to Physical Employment Status in military parlance. PES E means enlistees are fit for administrative duties only.

Isaac Tan will be sentenced on Oct 11.

His father, who was in the gallery, declined to comment when The Straits Times approached him.

On Friday, SC Tan's older son, Jonathan, 28, also surrendered himself in the State Courts after he pleaded guilty to similar offences earlier this year.

SC Tan and his two sons were seen walking into the courts at around 11.30am.

Jonathan Tan was sentenced to 16 weeks' jail in February after remaining outside Singapore without a valid exit permit between Dec 22, 2004, and May 4, 2015.

He returned to Singapore on May 5, 2015, and enlisted for NS on Jan 8 last year.

He had earlier indicated that he wanted to appeal against the sentence but withdrew the appeal on Sept 20.

In July, the High Court issued fresh sentencing benchmarks for NS dodgers, setting out four sentencing bands based on the length of default.

The benchmarks "amplified" punishments for those who default for longer periods, as this affects their fitness for service and the time they can serve as reservists.

In particular, for those who evade NS for seven to 10 years, the starting point is five to eight months' jail.

For remaining outside Singapore without a valid exit permit, Isaac Tan can be jailed for up to three years and fined up to $10,000.

Correction note: The headline has been amended to reflect the length of time Isaac Tan evaded NS.