No murder was committed.
Libby wasn't the murderer.
Libby was the guy who thought he learned the name of the victim from one source and the Daily Planet says he learned it elsewhere.
So, he's being prosecuted for a contradiction between two stories about where he learned the name of the murder victim.
If this were a murder trial, that would be laughed out of court.
No. It conceivably could get a directed verdict, but the indictment is facially sufficient, as far as I can tell.
It does us no good to circle the wagons. If anyone divulged classified material to reporters, he should be gone. If he revealed the name of a covert operative, he should be jailed. If he lied to the grand jury, he should be jailed. These go for everyone, from the file clerk to Pres. Bush himself.