We'll only see a conviction for the outing of Plame when White House staffers stop perjuring themselves and stone-walling the investigation.

In other words, never...

The real reason Libby was prosecuted is lost on many of the administration's defenders. Many have deluded themselves into believing that Libby's prosecution was some sort of political witch hunt.

This would have to be the first political witch-hunt in history where a Republican politico was prosecuted by a Republican prosecutor, sentenced and jailed by a Republican Judge, and refused bail by an appelate court, the majority of whom were Republicans.

Libby's prosecution wasn't a witch-hunt. Libby was prosecuted because he blocked Fitzgerald's investigation. Libby lied and stone-walled, preventing Fitzgerald from ever getting to the bottom of why Plame was outed.

The "why" is very important. This is because the Intelligence Identities Protection Act only allows prosecution of those who knowingly reveal the identity of a covert agent. Fitzgerald had to prove they knew, but he couldn't reach that level of proof without honest testimony from those involved.

But because Libby lied to the grand jury and FBI, because Karl Rove stone-walled and nearly found himself similarly prosecuted for perjury, Fitzgerald was unable to get enough proof to prosecute any IIPA violations.

Libby's lies probably saved some in the administration from prosecution under the IIPA. That is why Libby was prosecuted for perjury and why no one has been (or probably ever will be) charged for outing Plame under the IIPA.