It seems it is possible to be tried for framing a person even though there may not be sworn testimony, which would be tried as perjury. It seems tampering with evidence and obstructing an investigation are two of the counts that the ill-advised but well-intended roommate would face. At the end of the episode, the police did take her off in handcuffs, didn't they?
1999 Prosecutors and police go on trial in DuPage County, Illinois for conspiring to frame an allegedly innocent man, Rolando Cruz, ... in 1983. Cruz spent 10 years on death row before his acquittal at his third trial in 1995. All prosecutors and police are found not guilty, but the verdict is much less publicized by the media than the trial.
Obstruction of justice: http://tinyurl.com/7fp77ql