As Just One Minute (among others, including Rush Limbaugh) has pointed out, Senator Patrick Leahy is reaping what Patrick Fitzgerald sowed with the Libby prosecution.
Now, Congress is left with uncooperative witnesses who are unwilling to step into the perjury trap. From the Washington Post:
(Monica Goodling's) attorney, John Dowd, said the Senate inquiry amounts to a perjury trap for his client. "One need look no further than the recent circumstances and proceedings involving Lewis Libby," Dowd said.
I expect to see quite a few more people invoking their Fifth Amendment rights. When people are prosecuted for not remembering things right (or for not remembering things the way other witnesses did) and end up in jail, you aren't going to have people testifying voluntarily.
Eric at Is That Legal? explains that the Fifth Amendment protects the innocent as well as the guilty.
The Fifth Amendment privilege protects not just the guilty, but also the innocent, who fear that even their entirely truthful responses might provide the government with incriminating evidence from their own mouths. (Ohio v. Reiner, 532 U.S. 17 (2001) (dictum).) "The privilege serves to protect the innocent who otherwise might be ensnared by ambiguous circumstances." (Slochower v. Bd. of Higher Ed. of the City of New York, 350 U.S. 551, 557-58 (1956).)
A careful defense lawyer would be especially justified in advising his or her client to consider taking the Fifth in a highly charged political environment such as the Senate Judiciary Committee's investigation into the firings of U.S. Attorneys and the alleged minimization (dare we say "cover-up?") of the role of the Attorney General and the White House in those firings. It is important to remember that "a witness innocent of wrongdoing may well refuse to answer a question not because he fears conviction, but because he fears unfounded prosecution, a risk which every one runs at all times, theoretically at least." (Lewis Mayers, Shall We Amend the Fifth Amendment? 4 (New York: Harper & Brothers, 1959).)
The Akin Gump attorney probably did not need to broadcast his attack on the fairness of the atmosphere in the Judiciary Committee as he did; that does indeed smack of politics. But that doesn't mean that the advice he has given his client is bad. It is not. It is of course possible that the invocation of the Fifth is in bad faith, and that neither Ms. Goodling nor her attorney has any basis at all to fear her eventual prosecution, either for perjury, for making false statements, for obstruction of justice, or some other crime. But that strikes me as quite unlikely.
Whether Goodling has something to hide or not, in the highly charged political atmosphere of today, it's a smart thing not to give up anything.