A key prosecution witness returned to the witness stand today as the Rutgers University webcam spying trial resumed.

Former defendant Molly Wei faced cross-examination by the defense today. Wei testified about how Dharun Ravi apparently communicated among their friends that he was using his webcam to watch his roommate Tyler Clementi.

Wei claims she was surprised that some of their friends knew what she and Ravi had seen on the webcam.

According to Wei?s testimony, Ravi set his webcam to face Clementi?s bed and recorded Clementi kissing another man. Wei says Ravi then tweeted about Clementi's next encounter and encouraged friends to watch.

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

Tyler Clementi killed himself in September of 2010, just days after the webcam incident.

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