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Boon Tat Street death: Man who stabbed his son-in-law thrice gets 8.5 years’ jail

SINGAPORE — A man who stabbed his son-in-law thrice in broad daylight during a busy lunch hour and stood over him as he died was sentenced to eight-and-a-half years' jail on Monday (Sept 21).

Tan Nam Seng arriving at the State Courts on July 12, 2017.

Tan Nam Seng arriving at the State Courts on July 12, 2017.

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SINGAPORE — A man who stabbed his son-in-law thrice in broad daylight during a busy lunch hour and stood over him as he died was sentenced to eight-and-a-half years' jail on Monday (Sept 21).

Tan Nam Seng, 72, pleaded guilty last month to a charge of culpable homicide not amounting to murder by stabbing 38-year-old Spencer Tuppani near Boon Tat Street three years ago.

The judge said this was a "vicious and brazen killing" but noted the accused's major depressive disorder in effect at the time, as well as his "fast-deteriorating" health, which has weighed heavily on the judge's mind.

Tan's actions came after Mr Tuppani enacted a slew of business moves that Tan perceived as a ploy to cheat him of his company. They also lived in the same household, even after Tan's daughter discovered Mr Tuppani's affair with another woman and the couple was quarrelling frequently.

The elderly businessman, who had three daughters working in his company, was also suffering from major depressive disorder that significantly impaired his mental responsibility for the act.

On the day of the incident — July 10, 2017 — Tan saw his son-in-law eating at a coffee shop at 121 Telok Ayer Street.

Tan retrieved a knife from the company's office at Cecil Court before approaching the younger man, who was with three friends.

The accused told the younger man "you are too much" in Hokkien, before stabbing him three times in quick succession and following the victim as he stumbled away and collapsed in front of an F&B outlet.

Tan stood over his son-in-law and stopped others from helping him, telling them to "let him die" and that "I wish to kill him". Before the police arrived, Tan kicked the younger man's face twice, before calling his daughter.

He said to her: "I can't sleep at night. I have done it. I have killed him. Don't cry. I am old already. I am not scared (of) going to jail."

His daughter cried over the phone and told her father not to do anything, but Tan replied: "What's done cannot be undone."

The victim was found with three stab wounds and died of one of them, which perforated a heart artery.


The prosecution asked for 12 years' jail, saying that while Tan was suffering from major depressive disorder, there were "crucial" aggravating factors including the fact that it was "a revenge tragedy".

Tan exacted revenge on his son-in-law, in a "brutal, public and unprovoked killing" in broad daylight, said Deputy Public Prosecutor Lim Jian Yi.

The act was committed in "a very public place in the middle of the central business district", with a clear reaction from the public of shock and alarm.

Another aggravating factor was Tan's "cold and callous behaviour after the stabbing, preventing help from being rendered".

Mr Lim said Tan acted "quite rationally" in this case, and must be personally deterred "from taking things into his own hands in the future".

"There's also a general deterrence value, that the public knows you cannot take things into your own hands, even if there is a slight against your family, even if there is a commercial dispute," said Mr Lim.

He added that it is unknown whether the victim was going to cheat Tan of his business, and even if he was going to, "killing him is not the answer".

He argued for the court to give little weight to letters tendered to the court from Tan's grandchildren, asking for a lenient sentence.

"The fact is - for one thing, these three children are but three of the five children of Spencer," said Mr Lim. "Spencer has two children with another family, none of whom have said they've forgiven the accused."


Defence lawyer Wee Pan Lee said Tan is a divorcee who received only primary school education, beginning work as a coolie for a transport contractor in his early teens. 

He worked his way up to become a ferry clerk and later started his own shipping and transport cargo company at the age of 27. At its peak, the group of companies employed more than a thousand people, and Tan intended to groom Mr Tuppani to run the business with his daughters after retirement.

However, when Mr Tuppani handled the sale of the business, Tan and his daughter each received only S$450,000 instead of the S$1 million Tan said Mr Tuppani had promised. They also were not given the shares in the new company promised by Mr Tuppani, said the defence.

Over the years, Mr Tuppani hired his parents as employees and used company funds to pay for his younger brother's overseas education.

"He used company funds to fund his own lavish lifestyle ... for expensive cars, luxury watches and the upkeep of (his) mistresses," said Mr Wee.

Tan later discovered his daughter's marital woes with Mr Tuppani, who had been "involved in a string of extramarital affairs". Tan's daughter kept it from her father so as not to aggrieve him. She had conceived a fourth child in 2015 but "was forced to terminate this pregnancy by Spencer", claimed Mr Wee.

Tan began to realise that Mr Tuppani would not honour his word to return company shares to him and his daughter, and realised his son-in-law had been surreptitiously recording arguments with his daughter to use in divorce proceedings, going against his word to Tan not to fight over custody.

Mr Tuppani also suspended Tan's other daughter from the company and used vulgarities against Tan's ex-wife in an argument.

"It dawned upon the accused that he had fallen victim to Spencer’s ploy and it was planned all along to keep (the) shares and balance of cash for himself, and the constant reassurances and promises were lies and were all part of Spencer’s ploy to destroy the family," said Mr Wee.

Mr Wee said his client had no previous convictions, was not a violent person and had good relationships with his family and employees.

He also had a good relationship with Mr Tuppani before the incident, and was not just his father-in-law but his mentor, treating him like his own son and letting Mr Tuppani's mother stay in Tan's home.

Tan also suffered multiple health issues during the three years of his remand, contracting tuberculosis, suffering two heart attacks and undergoing bypass surgery.

Mr Wee said Tan's life expectancy is only about eight to nine years, and sentencing him to jail for longer than this is effectively a life imprisonment sentence.

For culpable homicide not amounting to murder, Tan could have been jailed for life. He cannot be caned as he is above 50. CNA

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