Republicans on the House Oversight committee believe that they can now compel Lerner to testify under a contempt threat because she gave a defiant opening statement in which she denied breaking the law.

Politico:

Lois Lerner might win the legal battle but she's prolonging the political war.

Instead of simply taking the scorn of lawmakers for a day, repeatedly invoking the Fifth Amendment to avoid self-incrimination, and then moving on, she chose defiance.

And her bravado has prompted House Oversight and Government Reform Committee Chairman Darrell Issa (R-Calif.) to say she has waived her constitutional right to not comment.

Now, he plans to haul the director of the IRS's tax-exempt department back to the committee for questioning.

"When I asked her her questions from the very beginning, I did so so she could assert her rights prior to any statement," Issa told POLITICO. "She chose not to do so -- so she waived."

Lerner shocked the committee room in the opening moments of Wednesday's hearing by delivering an opening statement denying any wrongdoing and professing pride in her government service.

"I have not done anything wrong," said Lerner, who triggered the IRS scandal on May 10 by acknowledging that the agency had singled out conservative groups applying for tax exemptions. "I have not broken any laws. I have not violated any IRS rules or regulations, and I have not provided false information to this or any other committee."

Beyond that, she refused to answer the committee's questions, immediately triggering a debate among panel members over whether she had just voided her Fifth Amendment rights.

Orin Kerr isn't so sure that Lerner has lost her Fifth Amendment rights:

The tricky part is how to characterize Lerner's testimony before she invoked the Fifth Amendment. On one hand, if you say that Lerner merely expressed her view that she is innocent but did not actually testify as to any facts, then you could say she did not waive her rights with her statement. Questioning would not be about the details of facts she already testified to, but rather would require her testimony on a subject she declined to testify about. On the other hand, if you say that Lerner's reciting the allegations and then denying them effectively testified about the allegations, then you could say that she did testify and did waive her rights. From that perspective, she already testified about "the subject" by saying that she did not violate any IRS rules or submit false testimony, and further questioning would be about the details of why she thinks that.

I'm not enough of a Fifth Amendment nerd to have strong views on which side is right. So I posed the question earlier today (based on press reports of what Lerner said, not the full transcript) to a listserv of criminal procedure professors that includes some serious Fifth Amendment experts. Opinions were somewhat mixed, but I think it's fair to say that the bulk of responders thought that Lerner had not actually testified because she gave no statements about the facts of what happened. If that view is right, Lerner successfully invoked her Fifth Amendment rights and cannot be called again. But this was not a unanimous view, it was not based on the full transcript, and there are no cases that seem to be directly on point. So it's at least a somewhat open question.

As Kerr points out, this isn't a criminal proceeding where a witness would be allowed to testify in their defense while taking the 5th on cross examination. But this being a congressional committee, Chairman Issa can rule however he wants to with regard to Lerner's rights and then sit back and see if the witness pursues legal remedies.

Whatever happens, it certainly is curious that the IRS manager who assured us that there was no political motivatiion in targeting conservative groups and it was just an administrative "short cut," would exercise her 5th amendment rights against self incrimination.