The press is afforded substantial freedom in covering judicial proceedings, and high profile criminal prosecutions such as that of Jerry Sandusky are no different. However, states are permitted to regulate what attorneys (both Prosecutors and Defense lawyers) say to the press while cases are pending. Generally, if there is a "substantial likelihood" that either side will be "materially prejudiced" by what is being said, a Court can issue limitations. Attorneys have a responsibility to avoid engaging in public debates/arguments to the detriment of either an accused defendant, or to the fair administration of justice.
Judge John Cleland issued a "gag order" to the attorneys involved in the Sandusky case, but also extended the order to law enforcement investigators, and anyone working on behalf of any of the attorneys in the case. The Judge's order basically permits only general statements about the case, and does not permit either side to state their opinion as to whether Sandusky is guilty or innocent, or to comment on the reputation, credibility or criminal history of Sandusky or any witness.
Since just about the entire nation is aware of this case, a change of venue (or a jury pool from a neighboring county - a "change of venire") is not necessarily going to help either side. In fact, Judge Cleland already denied the Commonwealth's motion for a change of venire. By issuing the "gag order," Judge Cleland is doing his best to avoid either side trying their case through the media, in front of the potential jurors. Trial is scheduled to commence on June 5, and will be one of the most closely followed trials in recent memory.