Boon Tat Street death: Man admits killing son-in-law who had affair and took over family business

Police officers at the scene of the crime on 10 July 2017. Tan Nam Seng, now 72, pleaded guilty at the High Court on Thursday (20 August) to a charge of culpable homicide by repeatedly stabbing his son-in-law Spencer Tuppani, 38, on the chest with a knife, intending to cause his death. (Yahoo News Singapore file photo)
Police officers at the scene of the crime on 10 July 2017. Tan Nam Seng, now 72, pleaded guilty at the High Court on Thursday (20 August) to a charge of culpable homicide by repeatedly stabbing his son-in-law Spencer Tuppani, 38, on the chest with a knife, intending to cause his death. (Yahoo News Singapore file photo)

SINGAPORE — A 72-year-old semi-retired businessman pleaded guilty at the High Court on Thursday (20 August) to a charge of culpable homicide over the stabbing of his 38-year-old son-in-law who took over the family business and had two children with a mistress.

Tan Nam Seng stabbed Spencer Tuppani on the chest with a knife thrice in broad daylight during lunch hour along Telok Ayer Street on 10 July 2017 with the intention of killing him.

Tuppani collapsed a few metres away along Boon Tat Street and died shortly after. One of the stab wounds went through his main artery.

When passers-by tried to help Tuppani, Tan told them, “don’t help him, let him die”, “he has come here to die” and “I wish to kill him”.

Tan also called his eldest daughter who was undergoing divorce proceedings and told 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 going to jail.”

After the stabbing, Tan placed the bloodied knife on a table, sat on a chair and waited calmly for the police. When officers arrived, he confessed to his crime.

Suffering from clinical depression

Tan was later found by a government psychiatrist to be suffering from clinical depression and experiencing a major depressive episode which significantly impaired his mental responsibility for the killing.

He was said to have had “overwhelming rumination and worries” about the well-being of his three daughters who worked in the family company.

Tan, who was brought to court from remand in Changi Prison on Thursday, appeared to have lost considerable weight since he was arrested. The hearing was translated into Hokkien to him by a court translator. Family members were also in court.

Deputy Public Prosectors Lim Jian Yi and Derek Ee, and defence lawyers Wee Pan Lee and Kyle Leslie Sim will argue on an appropriate sentence before Justice Dedar Singh Gill at a later date.

Tan faces life imprisonment, or a jail term of up to 20 years along with a fine. He cannot be caned as he is above 50.

Victim took over culprit’s company

Tan founded TNS Shipping in 1974 to provide port management services, and it later grew into various companies under the TNS name. His three daughters also worked for the TNS group of companies.

In 2005, Tuppani married Tan’s eldest daughter Shyller and began working for TNS Logistics. They later had three children.

Around 2008/2009, the TNS group of companies were consolidated into TNS Ocean Lines, of which Tan was chairman. Shyller was the firm’s commercial head, while Tuppani was a director who oversaw business expansion as well as sales and marketing.

From 2012, however, the company did not perform well. When things improved in 2016, Tuppani suggested to shareholders that it be sold to a bigger firm, GKE Corporation. Tan was also contemplating retirement, and left the sale to Tuppani. The shareholders eventually agreed on the sale.

In November 2016, in the lead up to the sale, Tuppani persuaded some shareholders – including Tan and Shyller – to assign him their shares to boost his stake in TNS Ocean Lines, so that GKE Corporation would not have control of it.

The sale went through the next month and Tuppani became the chief executive of the new company. Tan got some $450,000 from the sale of his shares but was unhappy with the amount as he had expected more, said DPP Lim.

In early 2017, Shyller found out that Tuppani had a mistress, with whom he had fathered two children. At the time, the couple were still living under the same roof as Tan. Shyller and Tuppani agreed to get divorced.

Divorce gets acrimonious

Tuppani moved out of the home around April, visiting only on weekends to spend time with the children he had with Shyller.

During these visits, the couple frequently quarrelled over issues such as custody and access of the kids. Tan often mediated between the two, and suggested arrangements for Tuppani to see the three children.

By the middle of June, the divorce became so acrimonious that Tan found out Tuppani was recording his arguments and conversations with Shyller. He suspected that his son-in-law wanted to use the recordings in divorce proceedings to get custody of the children and to avoid paying alimony. Tan told Tuppani to stop provoking Shyller further.

On 4 July, Tan’s daughter Sherry – who was the human resource manager at the company – argued with Tuppani’s personal assistant in the office over the alleged circulation of messages concerning Tuppani and Shyller’s family matters. Sherry was suspended from the company as a result.

DPP Lim said, “This incident troubled the accused greatly, as he believed that deceased would subsequently remove Shyller from the company as well. He also believed that this was part of (Tuppani’s) plan to cheat him of his business by divorcing Shyller after taking control of all their shares.”

The incident left Tan “feeling lousy and miserable” and he “ruminated excessively” about Tuppani’s actions and was unable to sleep at night, the prosecutor added.

Tan had arranged to meet Tuppani to discuss Sherry’s suspension a day after the incident. Tuppani agreed but later cancelled the meeting due to other business matters.

“As (Tuppani’s) former boss and father-in-law, the accused expected (Tuppani) to call him back to rearrange the meeting, but (Tuppani) did not do so. The accused felt that (Tuppani) was deliberately avoiding and disrespecting him,” said DPP Lim.

Culprit stabs victim in front of friends

On 10 July, Tan was driving to the company’s Cecil Court office at around lunchtime when he saw Tuppani having a meal with three friends at a coffee shop at 121 Telok Ayer Street. Angry that Tuppani was ignoring and avoiding him, Tan decided to confront him.

Tan got to the office at about 1.20pm, took a 22cm-long knife from the pantry and put it into his sling bag before walking to the coffeeshop.

Tan walked up to Tuppani with his left hand tucked under the cover of his sling bag and holding on to the knife handle. Tuppani called out “Pa” when he saw Tan.

DPP Lim said, “The accused asked (Tuppani) why he was not talking to the accused, and if he had anything to say. The accused then said ‘you are too much’ in Hokkien. During this brief conversation, (Tuppani) remained seated while the accused was standing in front of him.”

“Before (Tuppani) could respond, the accused pulled out the knife from his sling bag and stabbed (Tuppani) three times in his chest in quick succession, with the intention of causing (Tuppani’s) death.

Closed-circuit television footage of the stabbing was played in court.

Culprit tells passers-by to let victim die

Tuppani ran towards Boon Tat Street, where he collapsed outside a restaurant, A Poke Theory. Two of his friends called the police.

Tan followed Tuppani and caught up to him lying on the floor. When passers-by tried to help the victim, Tan pushed them away and told them not to help Tuppani.

Tan then walked up to Tuppani and forcefully kicked his face twice. He then placed the bloodied knife on a table, sat on a chair and waited for the police. CCTV footage of the incidents outside the restaurant were also played in court.

Tan also called Shyller to say that he had stabbed Tuppani thrice. When Shyller, who was crying over the phone, told Tan not to do anything, he replied, “What’s done cannot be undone.”

Culprit confesses to crime

Police officers arrived shortly after to find Tan seated calmly on the chair. Before they could say anything, Tan pointed to the weapon on the table about a metre away from him and said, “the knife is there”. He also pointed to Tuppani and said, “that’s my son-in-law.”

Ambulance paramedics found Tuppani lying unresponsive in a pool of blood. He was sent to Singapore General Hospital where he was pronounced dead at about 2.15pm.

While in a police car on the way to the Police Cantonment Complex, an officer asked Tan why the incident happened. “The accused replied that he was unhappy with how (Tuppani) had mistreated his daughter. The accused added that he had approached (Tuppani) a few times to sort things out since April 2017, but things did not change,” said DPP Lim.

Tan was initially charged with murder but this was reduced to culpable homicide after a government psychiatrist found that he was suffering from major depressive disorder, also known as clinical depression, and experiencing a major depressive episode at the time of the offence.

DPP Lim said the psychiatrist had found that, “The accused’s pervasive dysphoric state, diminished ability to concentrate, negative cognition of helplessness, as well as overwhelming rumination and worries about the well-being of his daughters would have adversely affected his impulse control and judgment at the time of the alleged offence, and significantly impaired his mental responsibility for the alleged murder.”

The punishment for culpable homicide is life imprisonment, or a jail term of up to 20 years along with a fine and caning. Only male offenders below 50 can be caned.

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