Originally posted by Davo: Neither. The prosecution of him for lying under oath.
1. Clinton was never prosecuted.
2. Clinton lied big time. He admitted it in a grotesque speech (in 1998, I think, about seven months after the Paula Jones investigation was concluded), in which he "apologized" to his family and the nation, without showing any real remorse at all, and attacked his accusers.
3. Clinton probably didn't commit perjury. Although he clearly lied (as that word is commonly used), his conduct probably did not meet the legal standards for perjury. See this: Legal analysis of the perjury accusations against Clinton.