President Donald Trump’s decision to fire FBI Director James Comey in the midst of the bureau’s investigation into his associates and campaign has contributed to “a crisis of public trust” that dates back decades, Sen. Ben Sasse said Monday morning.

Sasse (R-Neb.), in an interview Monday with “CBS This Morning,” called Comey “a fundamentally honorable man” whose actions during the 2016 election can nonetheless be fairly debated. But the FBI director, who Trump admitted last week he fired with the Russia investigation weighing on his mind, “is not supposed to be in a political chain of command and that’s the appearance of this situation and it’s timing,” Sasse said.

A handful of the Nebraska lawmaker’s GOP colleagues have called for the next FBI director to be an apolitical figure, an individual who would erase any doubt of partisanship at the bureau. In his Monday morning interview, Sasse agreed.

“I think we have a crisis of public trust right now and we need to restore that. The FBI’s a really special institution, and the American people need to know they can believe in it,” the senator said. “The FBI director has a 10-year term for a reason, because it’s supposed to be insulated from politics. I want to restore the rule of law but also the institutional conventions around that so there’s more trust.”

The “crisis of public trust,” Sasse said, dates back to the 1960s but has accelerated in recent years. He noted the depths to which the nation’s approval of Congress has sunk in polls and called the trend unsustainable. He predicted that the problem will only worsen as partisan media splinters further and caters to increasingly niche audiences. Trump’s firing of Comey, too, “contributes to that erosion,” Sasse said.

Asked at the end of the interview if he would consider mounting a primary challenge against the president in 2020, Sasse, who has been one of the GOP’s more willing critics of Trump, replied that “I’ve got the only two jobs I want: Raising three little kids and serving Nebraskans” but stopped short of outright denying a run.