IT HAS been established that President Trump used his official powers to press a foreign government for help with his reelection. Now, it appears that Attorney General William P. Barr might also be using the authority of his office for Mr. Trump’s political gain.

The Post’s Devlin Barrett, Shane Harris and Matt Zapotosky report that Mr. Barr has met with foreign intelligence officials abroad to advance an investigation on the origins of the probe into Russia’s 2016 election-year interference. The Russia inquiry culminated in March with a damning report from special counsel Robert S. Mueller III on Mr. Trump and his circle. The president wants the Justice Department’s latest investigation to prove that the Russia investigation was an anti-Trump conspiracy from the start.

Reports on the attorney general’s trips have not provided a definitive account of what he said in his overseas meetings, including in Italy and Britain. But they range from Mr. Barr providing introductions between foreign officials and John Durham , the U.S. attorney heading the investigation, to the attorney general saying he believed that the origins of the Russia probe were corrupt. Mr. Barr also encouraged Mr. Trump to make phone calls to foreign leaders, including Australia’s prime minister, urging cooperation.

This story is not as alarming as the news that Mr. Trump secretly pressed Ukraine to produce dirt on Joe Biden and his son Hunter. The Justice Department’s investigation into the Russia probe’s origins was announced publicly, and Mr. Durham is a credible, career prosecutor who presumably could conduct a fair investigation. It might even prove worthwhile if it can put to rest groundless conspiracy theories peddled by Mr. Trump and his followers — such as that Ukraine, rather than Russia, hacked the Democratic National Committee.

But these presumptions come into doubt when the attorney general and president are so personally involved. Mr. Durham’s reputation is no comfort if Mr. Barr is directing the investigation. The extremely unusual diversion of the attorney general’s precious time to a single investigation, let alone one on the margins of legitimacy, makes it only the more suspect. His involvement and that of Mr. Trump implies the desire for a conclusion the known facts do not support.

The Russia probe’s origins have already been examined by Mr. Mueller, congressional investigators and an aggressive, independent press. It is undeniable that Russia intervened in the 2016 election to help Mr. Trump, that Russian cutouts interacted with people in Mr. Trump’s circle and that multiple Trump confidantes lied to investigators. Mr. Trump nevertheless insists, without evidence, that the Russia probe was a “hoax” and has all but ordered his attorney general to find evidence that casts doubt on these conclusions.

It would be easier to trust Mr. Barr’s intentions if he had not burned his credibility early on in his tenure, pre-spinning the release of Mr. Mueller’s Russia investigation report with a dishonest summary of its findings. He then accused the U.S. intelligence community of “spying” on the Trump campaign. Mr. Barr has used the imprimatur of his office to promote Mr. Trump’s favored narratives. Now, he appears to be using the investigative powers of the Justice Department to advance that agenda — no matter how baseless.

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