In an interview to air Sunday on "Face the Nation," Rep. Trey Gowdy, R-South Carolina, excoriated Congress for having "proven itself incapable of conducting serious investigations."
Congressman Gowdy, who is not seeking re-election, also voiced support for special counsel Robert Mueller's investigation.
"I'm glad we have Bob Mueller," Gowdy told Brennan, "I'm glad we have an independent ball-and-strike caller."
A former federal prosecutor himself, Gowdy has taken part in several House investigations. He is perhaps best known for his role in the controversial Select Committee on Benghazi, which yielded key revelations over Hillary Clinton's use of a private email server.
Gowdy has long denied allegations that the Benghazi committee's work, which Democrats attacked as a "witch hunt," had any partisan purpose other than fact-finding. Gowdy took a similar tack in his interview with Brennan.
"Serious investigations don't make up their mind first, and then go in search of the evidence to validate your previously held conviction," Gowdy said.
Asked if he included the House intelligence committee in his criticism, Gowdy replied "absolutely," adding that "congressional investigations leak like the Gossip Girls."
Gowdy has played an integral role on the intelligence committee, which has seen an escalation of partisan hostilities in the wake of the controversial so-called Nunes Memo.
By February, bipartisanship had so eroded that Republicans floated an unprecedented division in the committee: constructing a physical wall. The planned partition would have divided the group's secure spaces to separate GOP and Democratic staffers.
"I mean, they're terrible, and I would be telling you that if I were staying in Congress, they are just not serious," Gowdy told Brennan of congressional investigations, saying that "serious investigations don't leak."
Congressman Gowdy appears this Sunday on "Face the Nation" with Senator Tim Scott, R-South Carolina, to discuss their new book "Unified."
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