NEW BRUNSWICK - A Rutgers University computer system manager says it appears the computer of Dharun Ravi was used in two video chats on Sept. 21, 2010, days ahead of Tyler Clementi's suicide.

Rutgers network analyst Timothy Hayes testified today that it appears Ravi's computer was in webchats with other students between about 7 and 8 p.m., and that it went dark for about two hours later that night.

Hayes says there's no data about Sept. 19, 2010, the night prosecutors say Ravi and another student viewed snippets of Clementi's dorm room encounter with another man. Hayes said the university does not save communication between computers within the same dormitory.

Investigators also say a search of Clementi's computer revealed that in the last two days of his life, he visited Ravi's public Twitter page 38 times. The page included tweets about Clementi's dorm room encounter.

Clementi jumped to his death from the George Washington Bridge in September of 2010, just days after the alleged spying.

Ravi faces 15 criminal counts, including invasion of privacy and bias intimidation.

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