Authorities say 19-year-old Dharun Ravi used a webcam last year to spy on roommate Tyler Clementi's intimate encounter with another man in September 2010.
Clementi killed himself shortly after that and became a touchstone for a national conversation about how young gays are treated.
Ravi's lawyers say they want the charges dismissed. They argue that prosecutors did not present a full and fair picture of what happened to the grand jury that indicted him earlier this year.
And if the case goes forward, they want more evidence, including about the other man involved.