THE family of Dr Shane Todd, an American researcher who died under disputed circumstances in Singapore last year, will not give a United States law enforcement agency two pieces of evidence that could shed light on his death.

The Singapore police had asked for the US Federal Bureau of Investigation (FBI) to examine the pieces of evidence because the family was unwilling to hand them over to local authorities.

Yesterday, Dr Todd's father, Rick, told US media: "We are not willing to participate in this because the Singapore police have limited the scope of the FBI's investigation."

He said the family would comply with the request by the Singapore police only if the FBI had "full involvement" in the probe. The two pieces of evidence are a hard drive that supposedly contains Dr Todd's work files, and a 2002 psychological report on Dr Todd when he was in university.

Dr Todd, 32, had worked for the Singapore Institute of Microelectronics before he was found hanged in an apparent suicide in his apartment last June. His parents believe he was murdered over his research at the institute.

Separately, the US Embassy in Singapore yesterday confirmed that US Senator Max Baucus met US Secretary of State John Kerry to discuss the matter. It did not comment on what was said at the meeting. The senator's office and the Todd family could not be reached by press time.

Senator Baucus met Dr Todd's family last week and Singapore's Ambassador to the US Ashok Kumar Mirpuri this week.

A spokesman for the senator's office told The Straits Times on Wednesday the senator will "continue doing everything in his power to get to the bottom of this case".

FENG ZENGKUN