Darinne Ko Wen Hui, the key witness in the sex-for-grades case against a state university law professor, told investigators she had been pregnant and had an abortion, the court heard on Wednesday.
"I found out that Darinne Ko was already cooperating with the investigations that confirmed sexual relationship, gifts and had told us about her pregnancy and abortion," Bay Chun How, chief special investigator for the Corrupt Practices Investigation Bureau said on the witness stand.
In her testimony last week, Ko said she had sex for the first time with Tey on 24 July 2010.
Bay said he learnt that on 2 April 2012 after getting back to the bureau's headquarters as he could not find the accused, National University of Singapore associate law professor Tey Tsun Hang,41, at work or at home.
The investigator also found out that Tey was in one of CPIB's interview rooms and hence proceeded to interrogate the then suspect.
The prosecution's seventh witness said the purpose of the interview was to confirm if Tey had sexual relationships with his students, if he received expensive gifts from them and if there were any reasons for the sex and gifts.
Tey appeared "frank, forthright, helpful" when the questions covered his background but when he was told of the allegation against him he became silent," Bay said.
Tey looked down on his tie and when he lifted up his head his eyes were red and he was tearing, the investigator added.
The law professor then refused to answer questions and stated that he "expected this day to come", Bay disclosed.
Defending himself, Tey has contested the admissibility of his six CPIB statements as they were made under duress.
Tey faces six charges of corruptly obtaining gratification in the form of sex and gifts from Ko in exchange for better grades.
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