A 36-year-old engineer who killed his girlfriend six years ago on Valentine’s Day, was spared the gallows when the Federal Court ruled he was of unsound mind at the time.

Court of Appeal president Justice Ahmad Ma'arop said the defence managed to prove on the balance of probabilities under Section 84 of the Penal Code that Cheong Teik Keon was of unsound mind.

Cheong was found guilty by the George Town High Court in 2016 and sentenced to death for the murder of Tan Ching Chin in Seberang Prai, Penang at 8.40am on Feb 14, 2013.

He had stabbed Tan three times and then tried to kill himself by stabbing himself four times.

A psychiatrist, who testified at the trial, said Cheong had a romantic and idealistic notion that he and his girlfriend would be reborn in heaven as lovers.

The decision was upheld last year by a three-member Court of Appeal bench before today's decision which ironically falls on Valentine's Day.

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"We uphold the conviction, but commute the death sentence for him to be kept at the mental asylum in Hospital Bahagia, Perak under the pleasure of the ruler (governor) of Penang," said Justice Ahmad.

Sitting with Justice Ahmad were Chief Judge of Sabah and Sarawak, David Wong Dak Wah, and Federal Court justices Ramly Ali, Alizatul Khair Othman Said and Rohana Yusof.

Cheong was represented by counsel Hisyam Teh Poh Teik, while DPP Asmah Musa appeared for the prosecution.

Cheong has been imprisoned at Tapah prison since 2013.

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