WASHINGTON Sally Yates testimony before a Senate subcommittee on Monday was highly anticipated. It would be the first time the public would get to hear an inside, on-the-record account of the Justice Departments warning to the White House about former National Security Adviser Michael Flynns interactions with a Russian government official.

The testimony of Yates, who was acting attorney general for the first 10 days of Donald Trumps presidency, was compelling. She recounted meetings with White House Counsel Don McGahn about concerns that Flynn could be compromised by the Russian government .

But the hearing also showed how political grandstanding, well-crafted aspersions and off-topic questions can weaken congressional investigations into such a crucial topic.

Yates, a 27-year Justice Department veteran, was confirmed as deputy attorney general during the Obama administration by a Senate vote of 84-12. Nevertheless, several Republican senators on Monday attempted to smear her as a partisan Democrat.

Sens. Ted Cruz (R-Texas) and John Cornyn (R-Texas) questioned her about a decision that led to her swift termination: instructing Justice Department attorneys not to defend Trumps first executive order because she believed it unlawfully targeted Muslims. (That line of questioning may have backfired: Yates wound up revealing that DOJ Office of Legal Counsel attorneys who signed off on the text of the executive order had been instructed not to tell her about it, and that she learned about it from news accounts.)

Sen. John Kennedy (R-La.) asked if Yates or former Director of National Intelligence James Clapper, who testified alongside her, had ever leaked information to the press. When they denied it, Kennedy followed up with Yates, asking if she knew of anyone at the Justice Department who had leaked to reporters.