Key witness tells court in sex-for-grades trial she liked law prof as a friend

The law professor on trial for corruption in a sex-for-grades case will defend himself in court. 

Tey Tsun Hang, 41, made the request in an unexpected twist minutes into the trial on Thursday morning.

Confusion and disagreement arose over this request and the matter took an hour to be sorted out. 

Tey, who came to court in a grey pin-striped suit, then changed into his court dress as he prepared to defend himself. 

Ninety minutes into the trial, key prosecution witness Darinne Ko Wen Hui was called to the stand. 

The 23-year-old former student of Tey gave her account of how she came to give her him a Mont Blanc pen. 

She said she liked Tey as a friend and had given him the 740-dollar pen as a belated birthday gift in May 2010. 

The court heard that as the two interacted more frequently, Tey would meet Ms Ko for lunch about two to three times a week. 

He would pick her up from her workplace and pay for the lunches. 

Tey, a National University of Singapore (NUS) professor who has been suspended, faces six corruption charges of allegedly showing favour to Ms Ko between May and July 2010. 

He's accused of obtaining gratification in the form of sex on two occasions, as well as items such as a Mont Blanc pen, an iPod and shirts.

These were said to be inducements to show favour in his assessment of Ms Ko's academic performance. 

The trial continues.