The prosecution's case

The trial of both Lim Beng Hai and Michael Tan began at the High Court on 18 February 1985. Lim was represented by Freddy Neo while Tan was represented by M. Puvanendram, and Edmond Pereira of the Attorney-General's Chambers (AGC) was in charge of the prosecution. Justice Abdul Wahab Ghows and Justice L P Thean were the two trial judges assigned to preside the trial hearing. At the start of the prosecution's case, it was revealed that Tan first rented the flat on 1 January 1983, and during the three months he spent living there, he often got into arguments with Soh over Tan not paying the rent on time and her demand that he move out, and it was opined by the prosecution that after the quarrels over rent, Tan formed the intention to rob and kill the victims, due to his need for money to buy drugs, and roped Lim in for his robbery plan. Despite the fact that Tan already had a home and married with two daughters, he rented the room for the purpose of selling and smoking heroin.^[14]

One of the witnesses, Sreedharan Udayakumar, an Indian friend of Tan, testified that on the night of the killings, Tan frantically came to his home to seek shelter and asked him to store a radio cassette recorder and video recorder. When Udayakumar asked him what happened, Tan admitted he robbed his landlady Soh and her two children, but they died because, according to Tan, it was Lim who killed all three of them.^[15][16][17] Another doctor, Dr Naranjan Singh, testified that he heard Tan admitting he was part of the robbery, but he stated he only wanted to rape Soh but his friend Lim had killed the victims and even stole from them. He also observed both Lim and Tan suffering from moderate to severe drug withdrawal symptoms.^[18]

Professor Chao Tzee Cheng, the senior forensic pathologist who conducted the autopsy on the victims, told the court that the victims had been stabbed during the alleged robbery. He demonstrated through a female officer's help on how the victims were killed. He firstly showed the court how the adult victim Soh was killed. He told the court that based on the blood splatters on the wall and height of the stains from above the ground, and the feet of Soh being below the bed, it was likely that Soh was in a kneeling position when she was stabbed inside the bedroom, and the scratch marks on her neck showed that her assailant was using one hand to grip onto her neck to strangle her during the stabbing. Professor Chao also said that by sequential order, either Tan or Lim or both killed Soh first before they laid their hands on the children, because he noticed that the bodies of both Jeremy Yeong and his sister Joyce fell onto and above the body of their mother. Professor Chao said the bruises on Jeremy's face was likely due to someone clasping the boy's mouth with the hand, which gave rise to the possibility that there was more than one assailant at the scene and that one of them killed Soh while another restrained the children, before they killed the two children as well.^[19]

Tan's defence

Tan elected to go to the stand to give his defence. However, he suffered from severe drug withdrawal symptoms right before the start of his defence phase, hence the trial was postponed for a month before Tan fully recovered.^[20] On the stand, Tan challenged the validity of his statements, claiming he did not make them voluntarily, claiming that he was under the influence of drugs when he made the statements, which he only made for the sake of getting drugs.^[21][22] Although the police officers denied it and stated Tan made the statements voluntarily,^[23] the trial judges ruled that Tan's statements were inadmissible as evidence, since narcotics officers corroborated his story that he found heroin on him at the time of his arrest and Tan had some withdrawal symptoms before making the statements, which made them doubt that he gave his statements voluntarily and in a full conscious state. Also, due to Tan's allegations that a prison officer supplied him the drugs, a 29-year-old prison warden, who was a Malaysian on a work permit, was found to have supplied heroin to Tan and other inmates, but due to insufficient evidence to formulate a charge against him, the ex-warden was indefinitely detained without trial.^[24]

Tan admitted to the court that he rented a room in the flat in January 1983 under an assumed name for the sole purpose of smoking heroin, as his wife always reported him to the police when he used drugs at their Toa Payoh apartment. Tan claimed that it was Lim who killed the children and their mother. He testified that on the day of the murder, his only intention was to rob the family while Lim wanted to rape Soh. Tan claimed that after ransacking the flat and packing up the valuables he stole from the flat, he heard screams coming from the room, and he saw the children lying motionless with blood on their chest and backs. He also saw the children's mother struggling with Lim, who was armed with the knife. According to Tan, he went there to break up the fight between Lim and Soh and during the scuffle, he witnessed Soh running towards Lim, but she got stabbed into the neck, as a result of her accidentally running into the knife Lim held in his hands.^[25][26] By his admission, Tan claimed he spent more than $2,000 a month on heroin and even trafficked drugs to maintain a stable income, and he thought he could become a millionaire should he never consumed drugs.^[27][28] Tan steadily denied the prosecution's contentions that he had intentionally killed Soh and the children despite their pleas for mercy and fabricated his account.^[29]

Lim's defence

Lim also elected to give his defence. He denied that he stabbed the victims, and claimed that Tan was responsible for the killings. He stated that he was a regular visitor to Tan's rented room, often going there to buy drugs and smoke heroin. He recalled that on the day they killed the children and Soh, Tan expressed his unhappiness that Soh pestered him about the rent, and suggested robbing Soh since he needed money. Lim decided to join despite declining the offer at first, and he also testified Tan wanted to rape Soh. However, during the execution of the robbery plot, Lim ran outside the flat while Tan was struggling with Soh inside the living room with the two children crying in fright nearby.^[30][31][32]

Prosecution's rebuttals

The prosecution in turn, argued that there was no doubt that the two defendants were culpable of the "brutal and wanton" killings of the Yeong children and Soh. Pereira, who made the prosecution's arguments, also highlighted that the men's accounts of how the killings occurred were inconsistent with medical evidence, which described the victim Soh having been stabbed while in a kneeling position rather than standing (like Tan claimed) or lying down (like Lim claimed), and that the children were being restrained at the same time of Soh's stabbing, which could be reasonable inference that more than one person had been responsible for killing the three victims, and not committed by one person. He also stated that both men had tried to fabricate stories to deflect blame from themselves, and hence their testimonies should be rejected, and Pereira therefore urged the court to convict both men of murder. The verdict was scheduled to be given on 10 April 1985.^[33][34]

Appeal processes

On 18 May 1987, both Lim Beng Hai and Michael Tan lost their appeals to the Court of Appeal against the death sentences they received for killing Soh and her children. Without calling for the prosecution's submissions, the three judges - Chief Justice Wee Chong Jin, Justice F A Chua and Justice Lai Kew Chai - rejected the men's claims of diminished responsibility since both men were not under the influence of drugs and both were fully aware of their wrongdoings and able to differentiate right and wrong.^[42][43][44]

The men later applied for special leave to appeal to the Privy Council at London in a bid to overturn their sentences, but in 1989, the men's applications were all rejected and thrown out by the Privy Council.^[45]

Tan's death

On 8 May 1990, while he was in solitary confinement at death row pending execution, 37-year-old Michael Tan Teow was found dead inside his one-man cell at Changi Prison by a warden. Despite efforts by prison officers to revive him, Tan was pronounced dead at the scene by paramedics.^[46] At the time of his death, Tan was survived by his wife, two daughters (aged 18 and 14 respectively at this point), his elderly mother and Jewish stepfather.^[47] According to Tan's 58-year-old mother, she felt regret for her son going astray due to lack of parental love, and stated she never knew about her son's crime until she read the paper. She revealed that her first husband abandoned her when Tan, who was her only child, was merely one month old, and thus she entrusted her child to his grandparents while she went on to marry a Jewish man and got into contact less and less with her son, whom she last visited in jail during the Chinese New Year season of 1990.^[48][49]

On 26 September 1990, during a coroner's inquiry into Tan's death, State Coroner Yap Chee Leong recorded a verdict of suicide, concluding that Tan had died as a result of an overdose of prescription pills, which were meant for his hypertension. It was not known how long did Tan hoarded or accumlate the large amount of drugs he consumed before his death by overdose. With Tan's death, his accomplice Lim was the only person left awaiting execution for the Ang Mo Kio murders while his death warrant was underway to facilitate the date for him to face the hangman's noose.^[50][51]

Lim's execution

On 5 October 1990, more than seven years after committing the murders at Ang Mo Kio, 33-year-old Lim Beng Hai was hanged at dawn in Changi Prison.^[52][53]