He was arrested for touching the schoolgirl on a bus in 2017.

But less than a year later, while out on bail, the man spotted the same girl on the same bus service and touched her again.

Yesterday, Ho Ah Chye, 53, was jailed for five months on two counts of using criminal force on a person with the intent to outrage modesty, with a third charge taken into account.

On Sept 18, 2017, the then 13-year-old girl, who was in her school uniform, fell asleep on bus service 3 as it was headed for Punggol Bus Interchange.

Ho, who was then a coffee shop assistant, was sitting next to her before she fell asleep.

When she was asleep, he placed his hand on her left thigh. Feeling uncomfortable, the girl moved away from him.

But a while later, he used his hand to rub the victim's thigh over her skirt.

The girl sought help from another passenger, and Ho then attempted to alight but was stopped by the bus captain.

He was later arrested and released on bail.

On Aug 16 last year, the same victim, now 14, boarded the same bus service.

Ho, who boarded at another bus stop, recognised her. He sat next to her again, placing his bag on his lap and hugging it with both arms.

The girl also recognised him but did not know what to do.

Ho used his elbow to rub against her ribs five times, each time lasting a few seconds.

The victim then left her seat to inform the bus captain and called the police.

In mitigation, Ho's lawyer Chooi Jing Yen said his client has limited understanding of the consequences of his actions due to a mental disability.

Ho was assessed in 1998 to have a low IQ of 65, and psychiatric reports showed he has some form of intellectual disability.

Mr Chooi added that Ho has never had an intimate relationship with a woman and thus may have difficulty dealing with his sexual impulses.

He also told the court that Ho has since taken steps to prevent a repeat offence by attending rehabilitative sessions.

He asked the court for a sentence of five months' jail.

But Deputy Public Prosecutor Nicholas Lim said there were aggravating factors such as the offences being committed on public transport.

He added that Ho was on bail when he committed the second offence and asked for eight months' jail.

During sentencing, District Judge Eddy Tham said that while there were aggravating factors, he noted that Ho has intellectual disability and there were rehabilitative efforts made to prevent a repeat of the offences.

For using criminal force on the girl when she was under 14, intending to outrage her modesty, Ho could have been jailed for up to five years, or fined, or both.