Lewis Libby has resigned as the top adviser to Vice President Cheney.
The announcement was made after Libby was indicted today on charges of obstruction of justice, making false statements and perjury in the CIA leak case.
If convicted on all five counts, Libby could face as much as 30 years in prison and more than $4 million in fines.
Libby has worked in relative obscurity, but he'd been considered one of the Bush administration's most influential advisers because of his proximity to Cheney.
Cheney is one of the most powerful vice presidents in history, and a trial could give the public a glimpse into his influential role in the West Wing.