Mr Goh Ho Leong was in the cubicle of a public toilet 21/2 years ago when a man suddenly pushed open the door.
Angered by this, the unemployed 52-year-old challenged the intruder and his friends to a fight.
In the brutal clash that followed outside the toilet at Tiong Bahru Park, Mr Goh was left with multiple injuries, including a fractured skull and bleeding in the brain. He died two days later in hospital.
On Friday, the six men who beat him to death were convicted of culpable homicide not amounting to murder.
The men are Anandraj Manimaran and S. Karthikesu, both 21; twin brothers Muhizin Khan and Segu Jamaldeen Nafil Mohamed, and Suriya Thankamany, all 20; and Abdul Samad Mohamed Kasim, 25.
The High Court heard that the six men, and four others, met at the park on the night of March 8, 2011, to chat and drink. They sat near a group of men, who later became unhappy with their presence.
To "resolve" the dispute, Segu, Abdul Samad and one other member of their party went to the public toilet nearby with part of the other group. Segu wanted to check if they were alone and pushed open the door of one of the cubicles, which was occupied by Mr Goh.
The two men argued. Mr Goh told Segu to wait and left the toilet. He returned later with a friend and a bicycle chain.
The victim was outnumbered, but an eyewitness heard him say "one to one" to the group. At this point, all six men started assaulting Mr Goh, who fought back with the bicycle chain.
They punched and kicked Mr Goh and continued to do so even after he fell, with Muhizin and Suriya using glass bottles to hit his head and face.
They left after joggers in the park shouted at them.
The other four in their group - including a girl who was 16 at the time - were also charged over the matter. They are understood to have been given discharges not amounting to an acquittal.
Deputy Public Prosecutors Mohamed Faizal and Puspha S. pushed for jail terms of between seven and eight years plus six strokes of the cane for Muhizin and Suriya. For the others, the DPPs asked for six to seven years in jail and six strokes.
They noted the victim's injuries and that the incident had taken place in full view of the public, in a park meant for recreation.
But defence lawyers Jeyapalan Ayaduray, Ramesh Tiwary, S.K. Kumar and Josephus Tan pleaded for leniency for their respective clients, highlighting the lack of premeditation and the provocative role the victim had played.
The six men, who pleaded guilty, will be sentenced on Oct 14.
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