Former projects manager Leu Xing-Long exchanged hundreds of text messages with a pimp negotiating over which prostitute to engage - and for how much.
Leu, then 28, also quizzed the pimp via text on how to set up his own vice business.
Yesterday, it all ended badly for the 31-year-old, who was jailed for 15 weeks for paying an underage prostitute for sex.
A district court had rejected his claim that he had been conscientious about ensuring the girl was over 18. She was actually 17.
Leu paid her $450 for services rendered at Hotel 81 Bencoolen on Sept 30, 2010.
The girl, now 21, was an escort listed on a website operated by the pimp, Tang Boon Thiew.
Leu is the 39th man to be dealt with over this online vice ring, out of the 51 men taken to court in 2012.
He fought one charge but, convicting him on May 5 after a six-day trial, District Judge Lim Keng Yeow said the text messages did not back up Leu's claims.
The judge said none of the texts showed any concern on the man's part over accidentally engaging a minor, or that he was consumed with abiding by the law as he claimed.
"The messages showed instead that his concern was mainly over which girl was available, at what price, and over details such as where and when to obtain the sexual service," the judge said.
He accepted the minor's evidence that she had not shown any part of an identity card to any of her clients.
Defence lawyers said in mitigation that Leu had not previously offended, adding that he was "sincerely remorseful and unconditionally apologetic" to the girl after learning her true age.
He is the seventh person to be convicted and sentenced after claiming trial.
Five others before him have received jail terms of between four and five months, and a sixth, an 18-month probation term.
The maximum penalty for the offence is seven years in jail and a fine.
This article was first published on May 27, 2014.
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