The American Bar Association went on trial as the accused at a hearing before the Senate Judiciary Committee on Wednesday.
The hearing centered on the ABA's judgment that Steve Grasz is "not qualified" to fill a seat on the 8th U.S. Circuit Court of Appeals.
Republican Sen. Ted Cruz of Texas appeared to raise a question about the future role of the ABA in evaluating judicial nominees for consideration by the committee.
"The notion of a nonideological organization is belied by its conduct," Cruz said, pointing to what he said was "clear bias in its evaluation" of Grasz, an Omaha attorney who served as chief deputy attorney general for Nebraska from 1991 to 2002.
Nebraska Republican Sen. Ben Sasse aligned himself with Cruz, suggesting the ABA is "a liberal advocacy organization (that is) masquerading as a neutral, objective evaluator."
There were clear indications that the committee will be sending President Donald Trump's nomination of Grasz to the floor of the Senate for confirmation on a strictly party line vote.
Democratic Sen. Dianne Feinstein of California suggested claims of ABA bias fall flat when one considers the organization has rated 49 of Trump's 53 judicial nominees as qualified or well-qualified even though many of them had "deeply conservative views."
But Republican Sen. Chuck Grassley of Iowa, the committee chairman, countered "it is quite clear that the ABA is not an independent, nonpartisan organization."
Pamela Bresnahan, a Washington attorney and chair of the ABA's standing committee on the federal judiciary, occupied the hot seat at Wednesday's hearing.
"It's a peer evaluation," she told the senators, a judgment as to whether a nominee "can be open-minded and be fair."
"The primary focus is freedom from bias," Bresnahan said. "His peers were concerned he could not divorce judging from his personal views."
"We're not here to become a political arm to anybody," she said.
"If you choose to ignore it, you ignore it, (but) we think we get it right most of the time."