Fitzgerald Says It Best.

From the OSC's press release:

“When citizens testify before grand juries they are required to tell the truth,” Mr. Fitzgerald said.

“Without the truth, our criminal justice system cannot serve our nation or its citizens. The requirement to tell the truth applies equally to all citizens, including persons who hold high positions in government. In an investigation concerning the compromise of a CIA officer’s identity, it is especially important that grand jurors learn what really happened. The indictment returned today alleges that the efforts of the grand jury to investigate such a leak were obstructed when Mr. Libby lied about how and when he learned and subsequently disclosed classified information about Valerie Wilson,” he added.