A Rutgers University student says a former dorm-mate who is charged with using a webcam to spy on his roommate encouraged her and other students to tune in.

Alissa Agarwal told jurors on Tuesday that she remembers Dharun Ravi sending a Twitter message daring friends to try to video chat with him the night his roommate asked to have their room to himself.

Agarwal says Ravi went to her room and showed her how his camera was set up to show his roommate's side of his room.

Ravi is charged with 15 criminal counts, including bias intimidation and invasion of privacy.

His roommate, Tyler Clementi, committed suicide days after the alleged spying.

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