The authorities will be considering how offenders such as mixed martial arts instructor Joshua Robinson, who had sex with two underage girls, may be "dealt with more severely through higher penalties", said Home Affairs and Law Minister K. Shanmugam yesterday .

His remarks follow the Attorney-General's Chambers' statement that the public prosecutor will not appeal against Robinson's four-year jail term. The 39-year-old American pleaded guilty to having unprotected sex with two 15-year- old girls and showing an obscene video to a six-year-old.

His sentencing last Thursday sparked strong public reactions, with the father of the six-year-old expressing disappointment online. A petition calling for harsher punishment was also started on Sunday.

"I can understand people's unhappiness," said Mr Shanmugam, who is on a working trip in Australia. In a statement in response to media queries, he added that Robinson's offences were "more serious" than a range of other cases involving sex with underage girls. He cited the cases of an 18-year-old youth who had sex with his 15-year-old girlfriend, and that involving 51 men who were charged with having sex with an underage prostitute. They were jailed for between four and 20 weeks each, he said.

"I have asked my officials to consider what approaches are necessary for offenders like Robinson to be dealt with more severely through higher penalties," said Mr Shanmugam.

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RESPECT DECISION In our system, decisions on prosecution, sentence to ask for, and appeals, are all within the discretion of the AGC. We need to respect the decision of AGC. HOME AFFAIRS AND LAW MINISTER K. SHANMUGAM

Currently, as the sex was consensual, the law does not provide for caning. He added that the original decision was "cleared at the highest levels - by the previous A-G himself, based on precedents from previous cases".

"In our system, decisions on prosecution, sentence to ask for, and appeals, are all within the discretion of the AGC. We need to respect the decision of AGC," he said.

"I do think that the sentences for such offences committed by Robinson need to be relooked at. That is why I have asked my ministries to study this," he added.

But he said it is premature to reveal what penalties are being considered.