Former Attorney General Sally Yates in a new op-ed called for Americans to embrace the values set out in the U.S. Constitution and to hold leaders accountable for telling lies.

Yates writes in USA Today about the importance of "objective truth," adding that it is up to the American people to hold political leaders accountable when they spread disinformation.

"We can debate policies and issues, and we should. But those debates must be based on common facts rather than raw appeals to emotion and fear through polarizing rhetoric and fabrications," she writes. "Not only is there such a thing as objective truth, failing to tell the truth matters. We can't control whether our public servants lie to us. But we can control whether we hold them accountable for those lies or whether, in either a state of exhaustion or to protect our own political objectives, we look the other way and normalize an indifference to truth."

Though the piece does not mention President Trump by name, Yates's focus on the importance of the rule of law and truth appears to take a dig at the president over the investigation into whether his campaign colluded with Russia.

"Democratic and Republican administrations alike, at least since Watergate, have honored that the rule of law requires a strict separation between the Justice Department and the White House on criminal cases and investigations," Yates writes. "This wall of separation is what ensures the public can have confidence that the criminal process is not being used as a sword to go after one's political enemies or as a shield to protect those in power. It's what separates us from an autocracy."

Many have suggested that Trump has obstructed justice in his approach to the investigation, in particular by firing FBI Director James Comey.

Trump also fired Yates, then-acting attorney general, after she refused to defend his first travel ban, saying that she had "betrayed" the government.

Yates writes that "we are not living in ordinary times," and urges Americans to aspire to the nation's founding ideals, such as freedom of speech and the rule of law.

"Over the course of our nation's history, we have faced inflection points - times when we had to decide who we are as a country and what we stand for," Yates writes. "Now is such a time. Beyond policy disagreements and partisan gamesmanship, there is something much more fundamental hanging in the balance. Will we remain faithful to our country's core values?"