Former Swiss banker Juerg Buergin, 41, was on Tuesday found guilty of having paid sex with an underage prostitute. In his oral judgment District Judge Eddy Tham found that Buergin had failed to raise a reasonable doubt as to whether sexual intercourse had taken place between him and the escort on Sept 29, 2010 and Jan 3, 2011.

In contrast, the girl - who cannot be named as she was a minor at the time - was a "forthright" and "convincing" witness who "did not have anything to hide or reason to embellish her evidence" against Buergin.

He found that the prosecution had proven its case beyond a reasonable doubt all the essential ingredients against Buergin.

He will pass sentence on May 8. The maximum penalty for each charge is seven years' jail and a fine.

Deputy Public Prosecutor Kavita Uthrapathy sought a sentence of at least six months on each charge. She said there was a 22-year age gap between Buergin and the minor. He did not ask nor check her age and did not exercise the due diligence expected from him by the law.

"This is especially disturbing considering the fact that she was represented as being only 18 years old and still under 'parental control','' she said. He was wilfully blind to the possibility that she might be younger than she was represented and he was reckless, she added.

In mitigation, defence counsel Selva K. Naidu said his client was not looking for an under-18 escort as most of his bookings were for older women.

Buergin was the first person to claim trial. Two other men have since gone on trial for similar offences. So far, 18 men have been jailed between eight and 16 weeks for having commercial sex with the girl, who had around 80 bookings with 64 men. Fifty-one men were charged.