New York, Mar 10 (IANS): Seven friends of Indian American student Dharun Ravi, charged with spying on his gay roommate, have testified they never heard the former Rutgers University student disparage homosexuals.

The testimony came as Ravi's lawyers began their defence Friday presenting a chorus of character witnesses and attacking the credibility, judgment and integrity of the police investigation, according to NYDailyNews.com

Ravi, 20, is on trial in Middlesex County Superior Court in New Jersey on charges of bias intimidation and invasion of privacy for using a webcam to spy on his gay roommate's tryst with another man.

The roommate, Tyler Clementi, became aware his sexual encounter had been viewed by others from reading Ravi's Twitter feed. Clementi jumped off the George Washington Bridge to his death on Sep 22, 2010.

Questioning the lead investigator Frank DiNinno, defense counsel Steven Altman elicited that the detective's office took a second statement from a key witness Lokesh Ojha after learning of his complicity.

Ojha has testified that he helped Ravi set up his webcam on Sep 21 for a second viewing of the two gay lovers, which never happened, and initially lied to police about his involvement.

In another line of questioning, Altman chipped away at the integrity of the state's central contention that Ravi was motivated by homophobia.

DiNinno said he had interviewed 30 people with knowledge of the webcam incident, and asked all of them if they ever saw Ravi display an anti-gay attitude, in words or deeds. None of them said they had.

Altman also asked detailed questions about whether witnesses were pre-interviewed and which witnesses gave multiple statements to police.