U.S. Sen. Chuck Grassley loves to tout his independence and bipartisanship. His rhetoric could soon be tested when the chairman of the Senate Judiciary Committee presides over nomination hearings for whoever is put up to replace ousted FBI Director James Comey.

Over the past year and a half, Grassley has leaned heavily on almost four decades of largely honorable service. Even that distinguished record is buckling under the weight of the interference campaign Grassley's running for the Donald Trump's White House, though.

Grassley is either the White House's lap dog or an honorable lawmaker. Under this administration, the two are mutually exclusive.

President Trump shocked the country when he suddenly sacked Comey last week because Comey didn't kiss the ring. Under the pretext of Comey's mishandling of Hillary Clinton's email scandal, Trump fired the man at the helm of the investigation into the possible collusion between Russian agents and the president's closest political advisers.

It's smells of an attempted cover up orchestrated by an administration neutered by the Russian probe's very existence. It's an assault on FBI independence. It's possibly a crime.

Several Senate Republicans rightly questioned the motives behind Trump's Nixonian purge. North Carolina's Richard Burr, chairman of Senate Intelligence Committee, called Comey's ouster "troubling," adding that it adds more confusion to his committee's probe into Trump's connections to Russia. Nebraska's Ben Sasse said the timing of Comey's ejection was "very troubling." Arizona's John McCain was "very disappointed." Some even called for a special prosecutor since, clearly, the Justice Department is tainted.

But not Grassley, the man soon tasked with ensuring Trump doesn't insert some political lackey. He immediately parroted the White House's line about Clinton's emails, an excuse that soon crumbled when Trump admitted it was the Russia investigation that fueled his decision.

Fun fact: Hillary Clinton is not president. Donald Trump is. Enough with the deflections.

It wasn't the first time Grassley carried water for the White House. Some days, he looks to be filling Trump's swimming pool one bucket at a time. Neither Supreme Court seats nor tax cuts are worth selling out the country.

Just last week, former acting Attorney General Sally Yates appeared before Grassley's Judiciary Committee and testified that she told the White House that then-National Security Adviser Michael Flynn had been compromised by the Kremlin, a warning the administration ignored for weeks. Yet again, Grassley had no interest in a potential threat to the republic, such as the Russian probe. No, Grassley wanted to know who leaked information about the Russian probe to the media, as if that's the real issue.

Trump even harassed and intimidated Yates on social media prior to her testimony. Grassley didn't even bother defending his witness testifying under oath from the shameful attacks. Instead, he badgered her precisely as Trump had directed.

Over the past few months, Grassley has forcefully advocated for Trump's various nominees and shutdown dissent from Democrats. He's repeatedly shilled the White House's spin on the controversy of the day. Like so many congressional Republicans, he's often remained silent as Trump beat, kicked and flogged the very norms that form the foundation of an entire system of government.

Ours aren't the rantings of some mob demanding Trump's immediate impeachment. They are not some political hit job targeting Iowa's senior senator. They are a reflection of legitimate, serious concerns about Trump's rampant narcissism, admiration for despots and disdain for the most fundamental political norms.

It's very possible Trump offers up a qualified nominee to run the FBI, someone who will take control of the investigation that could, ultimately, destroy his presidency. But it's also possible -- even likely -- that Trump puts forth yet another political minion who will quash what could be the most important investigation in a generation.

If that happens, it falls to Grassley, finally, to take these concerns seriously and acknowledge that Trump's paranoid flailing is neither normal nor sustainable.

The responsibility to guarantee the country gets the answers it needs now rests with Sen. Chuck Grassley. That's if he's half as independent as he claims.

This editorial appeared in the May 14 edition of the Quad-City Times, another Lee Enterprises publication.

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