The perjury trial of former baseball star Roger Clemens ended in a mistrial the judge blamed on prosecutors and said a “first-year law student” would have known to avoid.

The question of a new trial up in the air was left by U.S. District Judge Reggie Walton.

Walton called a halt to the trial under way after prosecutors showed jurors evidence that he had ruled out videotaped revelations that a teammate had said he did told his wife Clemens confessed to using a drug.