Dharun Ravi will face a new trial on some of the original charges, but not all of them.
He was assigned to live with 18-year-old Tyler Clementi at Rutgers in 2010.
Ravi secretly broadcast online images of Clementi in an intimate encounter with another man, and Clementi, a freshman in his first weeks at Rutgers, later jumped off the George Washington Bridge.
Ravi was convicted of bias intimidation, invasion of privacy and other crimes.
But the court tossed several bias intimidation counts against him due to a change in state law.
The other counts required a new trial, the judges decided.
Ravi faced up to 10 years in prison but was sentenced to probation plus 30 days in county jail.
Prosecutors were trying to get a stiffer sentence — arguing the sentencing judge overstepped his authority by imposing one so lenient.
Now that a new trial has been ordered, the prosecution’s sentencing case has been dropped.
Clementi’s parents have formed a foundation that addresses bullying and lesbian, gay, bisexual and transgender issues.
Tyler’s 2010 death started a national conversation about the treatment of young gay people.
His mother Jane Clementi earlier this year said the country had come a long way since his suicide.