Attorney General Merrick B. Garland defended on Wednesday recent Justice Department moves upholding Trump-era positions on controversial cases, vowing to continue to adhere to the rule of law regardless of political pressure.

“The essence of the rule of law is what I said when I accepted the nomination for attorney general,” Mr. Garland said at a budget hearing before the Senate Appropriations Committee, adding that his goal was to ensure that there was “not be one rule for Democrats and another for Republicans, that there not be one rule for friends and another for foes.”

Mr. Garland continued: “It is not always easy to apply that rule. “Sometimes it means that we have to make a decision about the law that we would never have made and that we strongly disagree with as a matter of policy.”

The Justice Department defended on Monday a legal position taken under the Trump administration in a case involving E. Jean Carroll, a writer who in 2019 publicly accused former President Donald J. Trump of sexually assaulting her 25 years earlier.

Mr. Trump denied the assault in an Oval Office interview and said that he could not have assaulted her because she was not his “type.” After Ms. Carroll sued him over the remarks, the Justice Department argued that Mr. Trump could not be held liable for defamation because he had made the statements as part of his official duties as president.

In the brief filed on Monday with a federal appeals court in New York, Mr. Garland’s Justice Department called Mr. Trump’s remarks “crude and disrespectful,” but said that his administration had correctly argued that he could not be sued over them.

Should the Justice Department prevail, Ms. Carroll’s lawsuit could be dismissed.

The appeal dismayed Democrats, as did another argument by the Justice Department in May when it sought to keep hidden a memo related to Mr. Barr’s determination that Mr. Trump had not illegally obstructed justice in the Russia investigation.

While the department released the first page and a half of the nine-page memo, it argued that the full document must remain out of view because it contained information that was part of the department’s decision-making process, and that such information could be lawfully kept secret.

Mr. Garland said that he was aware of the criticisms, but defended his actions.

“The job of the Justice Department in making decisions of law is not to back any administration, previous or present,” he said.