Subsequently, two of Bock's suspected killers, Tony Koh Zhan Quan (许展权 Xǔ Zhănquán) and Lim Poh Lye (林保来 Lín Băolái), surrendered themselves to the authorities and were charged with murder, although the third offender, Ng Kim Soon (黄金顺 Huáng Jīnshùn; alias Ah Soon or Philip Ng), remains at large till today.

Subsequently, at the end of the trial, Lim and Koh were found guilty of robbery with hurt and sentenced to caning and terms of imprisonment between 15 and 20 years.

[6] The police placed the names of Ng and Koh on the wanted list, and asked for the help of Malaysian authorities to trace their whereabouts.

[9][10] On 28 September 2004, both Lim Poh Lye and Tony Koh Zhan Quan stood trial for the murder of Bock Tuan Thong at the High Court.

[11] As of the time when both Lim and Koh stood trial, Ng Kim Soon, who was pinpointed as the mastermind of the case, remained at large for killing Bock.

[13] Daniel Sin, another prosecution witness, also told the court that when he was somewhere at Upper Serangoon, he was next to Bock's car and saw bloodstains at the headrest.

Dr Tan pointed out that one of the wounds on the right thigh was deep and it cut through the femoral artery, resulting in an excessive blood loss and it was sufficient to cause death in the ordinary course of nature.

While they were driving to the United Overseas Bank (UOB) at MacPherson, Ng forcibly asked Bock to write and sign three cheques with S$10,000 each.

Lim also said that the original plan did not involve causing any hurt to Bock but his attempt to escape caught them by surprise and it resulted in the stabbing.

In his judgement, Justice Choo stated that he was satisfied that the two defendants Lim and Koh never had the intention to commit the murder of Bock.

He said that it was not clear who was the person that inflicted the fatal wound based on the medical evidence, and accepted that the knives were used to just threaten Bock, which was what they planned all along.

Justice Choo also stated that there was no intention on the part of the trio to inflict any wounds that were sufficient to cause death, and Lim's purpose of stabbing the victim (either alone or with Ng's help) was merely to stop Bock from continuing to struggle or resist rather than taking his life, and with the possible accompanying factor of Bock's struggle during the stabbing and its impact on the severity of the wounds caused, Lim (and possibly Ng) never aimed specifically at the region of Bock's thigh to cut through his artery and cause him to die from an excessive loss of blood.

[29][30][31] In February 2005, the prosecution filed an appeal against the trial verdict,[32] seeking to overturn the two men's convictions of robbery with hurt and asked that the murder charges be restored after arguing that the trial judge had erred in law to acquit Koh and Lim of murder and cited that it was irrelevant to determine the purpose of stabbing Bock, as the more crucial question was whether there was an intention to inflict the knife wounds and whether the injury inflicted was sufficient to cause death, and also cited the common intention of the trio to commit armed robbery.

The three judges - Chao Hick Tin, Lai Kew Chai and Tay Yong Kwang - stated that in view of the evidence, there was no doubt that the two defendants Tony Koh and Lim Poh Lye had committed murder.

[38] As a result, the Court of Appeal allowed the prosecution's appeal, and found both 45-year-old Lim Poh Lye and 38-year-old Tony Koh Zhan Quan guilty of the original charges of murder, and sentenced both men to death, effectively overruling the trial decision and overturning both men's jail terms and robbery convictions.

[39][40] It was reported that Bock's wife accepted the verdict and she expressed that she would visit her husband's resting place to inform him of the appeal ruling.

Their lawyers argued that the prosecution had only the right to appeal in cases where they opposed an defendant's sentence or acquittal, and that both men were not acquitted of murder, since the original murder charges were merely reduced to lesser offences of robbery with hurt and the men were convicted of lower charges, and there was no pronouncement of an acquittal by the trial court.

However, the Court of Appeal agreed with the prosecution that the trial judge had found both Lim and Koh not guilty of murder, which was equivalent to an acquittal.

[42][43][44][45] After losing their final legal motion to escape the gallows, both Lim and Koh petitioned for presidential clemency to commute their sentences of death to life in prison.

[46] On 28 April 2006, 46-year-old Lim Poh Lye and 39-year-old Tony Koh Zhan Quan were both hanged at dawn in Changi Prison.