SINGAPORE - A 49-year-old man, whose courtroom antics included smearing faeces while he was in the dock, was on Wednesday (Feb 5) convicted and sentenced to 32 years' jail and 24 strokes of the cane for raping two teenage girls.

Isham Kayubi was found guilty of four counts of rape and two counts of sexual assault by penetration. It emerged in court that the part-time food deliveryman was jailed 4½ years in 2008 for sexual offences against four teenage girls.

Prosecutors drew parallels between his past and current offences, in which he separately lured two 14-year-old girls to his Jurong West flat and sexually assaulted them, in a short span of two weeks in late 2017.

Isham threatened to summon his "gang members" if the two victims did not comply with his demands, and also recorded the sexual acts on his mobile phone.

In sentencing, High Court judge See Kee Oon agreed with prosecutors that a deterrent sentence was needed, given that he was a repeat offender who preyed on young and vulnerable victims.

Deputy Public Prosecutor James Chew also told the court there is a "high likelihood" that separate action will be taken against Isham for his conduct in recent court hearings.

In August last year, when the case was originally slated for hearing, Isham exposed himself and urinated in the dock.

He was remanded for psychiatric evaluation and a report found that he was malingering and not mentally unsound.

The trial was rescheduled to start on Jan 14 but Isham - who has been taking laxatives for constipation - defecated in his clothes and refused to change out of his soiled prison uniform.

He then smeared faeces on a glass panel while court was in session.

He also mumbled incoherently when asked how he wished to plead to the charges, but by the third day of the trial, he was able to cross-examine prosecution witnesses.

However, when called to give his defence to the charges on the fourth day, he refused to respond.

He asked for more time to get a lawyer, claiming he had recovered from memory loss, but was turned down.

On the next court date, he was given more time to prepare closing written submissions after he said he had not received a copy of the transcripts.

On Wednesday, DPP James Chew argued that there was strong DNA evidence against Isham as his semen was found on vaginal swabs taken from one of the victims.

But Isham noted that there was another DNA profile found on the victim. "Who is the unknown male? That is the question we should ask here," he said through a Malay interpreter.

He maintained his innocence, claiming that the two victims fabricated evidence to falsely implicate him.

But Justice See said the prosecution has proved its case beyond reasonable doubt.

The judge found the victims to be credible witnesses who were candid and straightforward.

"I see no reason for them to fabricate or embellish their evidence, let alone falsely implicate the accused," he said.

The judge also noted that there was objective evidence in the form of footage from surveillance cameras at Isham's block, and video recordings and messages on Isham's phone.

"He offered no evidence, choosing not to testify or call other witnesses in support of his defence," said the judge.