The man's sentence was backdated to the date of his arrest.
An Indian-origin married man was sentenced to 20 years in jail on Monday for culpable homicide not amounting to murdering his girlfriend for having relationships with other men.
Upset about her relationships with other men, M Krishnan punched and kicked Mallika Begum Rahamansa Abdul Rahman, 40, who died on January 17, 2019.
Krishnan, 40, pleaded guilty in the High Court last week, "TODAY" newspaper reported on Monday.
His sentence was backdated to the date of his arrest.
Justice Valerie Thean noted that Krishnan had promised he was a reformed individual in 2018 in his mitigation (for another offence of abusing police officers), but continued to abuse his wife and girlfriend.
She also noted during the sentencing that although Krishnan's intermittent explosive disorder had some contribution to his violent actions, alcohol had also influenced the way he acted.
Justice Thean added that even though he was diagnosed with the disorder after the offence, "the accused knew he was susceptible to showing his temper in socially unacceptable ways" through his past brushes with the law.
Saying that she could not overlook his repeated domestic abuse against the women, the judge sentenced Krishnan to 20 years in jail.
For culpable homicide not amounting to murder, the maximum penalty is life imprisonment and caning, or a jail term of up to 20 years and a fine or caning.
In November 2015, Krishnan's wife caught him and his girlfriend drinking alcohol in the master bedroom of their marital home.
Upset, she uttered vulgarities at Krishnan and he then punched her in the face, before grabbing a whisky bottle.
Afraid that he would hurl the bottle at her, the wife apologised and later, obtained a personal police protection order against him.
Krishnan and Mallika continued their relationship all this while up until her death.
During their time together, Krishnan hit Mallika at least once in 2017 "over a trivial matter", court documents stated.
The abuse intensified at the start of 2019 after Mallika admitted to having sexual relations with several men, including when Krishnan was in jail in 2018, according to TODAY's report.
On January 15, 2019, Krishnan kicked and slapped Mallika in the face, punched her in the ribs and kicked her in the thigh.
This was after she confessed to cheating while they were drinking alcohol in the apartment they shared.
As she pleaded with him not to leave, he grabbed her by the neck and pushed her, causing her to fall and hit her head against a wardrobe.
She got up, stumbled to the kitchen and slumped in front of a cabinet. He told her to get up and when she did not, he pushed her forehead, causing her to hit her head against the cabin.
The next day, Mallika sought medical treatment at a hospital and was found with several bruises and abrasions.
While Mallika was at the hospital, Krishnan drank alcohol throughout the day.
At night, they spoke with Mallika's sister over the phone about Mallika's relationship with another man.
Feeling angry and frustrated over her various affairs, Krishnan assaulted Mallika again.
He slapped her face, grabbed her by her hair, and punched and kicked her.
After kicking her repeatedly while she was on the ground, he helped her to the bed and realised that she was not responsive or breathing.
He then called the Singapore Civil Defence Force at about 1:35 am and Mallika was pronounced dead later by the responders.
An autopsy found that she had died from a head injury, with several bruises on her scalp, back of her neck, face and around her body.
Several of her ribs were fractured as well.
During sentencing on Monday, Deputy Public Prosecutor (DPP) Timotheus Koh told the court that Krishnan had asked a friend to let him sleep in his apartment after the assault.
In the afternoon of January 17, 2019, Krishnan surrendered himself to police.
After his arrest, Krishnan was diagnosed with intermittent explosive disorder -- a condition where there are frequent impulsive anger outbursts or aggression -- which was found to have contributed to his offence.
However, the level of violence he inflicted on his girlfriend was "likely caused by the alcohol intoxication, adding to the intermittent explosive disorder", court documents showed.
The prosecution sought a sentence of 15 to 18 years in jail, urging the court to "send a clear message that the courts do not tolerate violence of this nature".
Koh said although Krishnan's mental disorder was diagnosed after the offence, he had a history of "socially unacceptable behaviour" involving violence while intoxicated.
This included Krishnan's mitigation plea in 2018 for being verbally abusive and spitting on police officers, where he acknowledged that alcohol had "severely clouded my decision at the time".
He also said Krishnan was referred for counselling due to the domestic violence that occurred from 2015 to 2016, and that his actions showed his "propensity for abusing his domestic partners".
Koh added: "No mitigating weight should be placed on whatever emotions that the accused was feeling after the deceased's confessions to him about her relations with other men.
"The accused is not in the position to punish the deceased for her purported infidelity." During mitigation, Krishnan's lawyer said his client had pleaded guilty early, surrendered to police and fully cooperated during investigations.
Krishnan had been controlling his alcohol intake -- drinking only on weekends when he was not working -- he added.
However, it was Mallika's relationships with other men that had "affected his judgement".
"He thought alcohol would assist him to cope with his feelings," the lawyer said.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)