President Donald Trump made public a letter from his tax attorneys on May 12 saying Trump’s tax returns from the past decade contain no undisclosed income from Russian sources.

That same day, Sen. Chris Murphy, D-Conn., found what was a too-good-to-pass-up irony about the firm Trump used to write the letter.

"Law firm @POTUS used to show he has no ties to Russia was named Russia Law Firm of the Year for their extensive ties to Russia. Unreal," Murphy said in a May 12 tweet. The post was certainly popular -- it has been retweeted 56,000 times as of the writing of this fact-check. It also elicited an eye-rolling .GIF from Sen. Bob Casey, D-Penn.

Law firm @POTUS used to show he has no ties to Russia was named Russia Law Firm of the Year for their extensive ties to Russia. Unreal. — Chris Murphy (@ChrisMurphyCT) May 12, 2017

Given the continued interest in possible links between Trump and Russia, we decided to look into Murphy’s statement.

Morgan Lewis earned 'Russia Law Firm of the Year' title

Trump’s tax lawyers are partners in the Washington, D.C., office of Morgan Lewis, which employs some 2,000 attorneys in 30 cities around the world, including 40 lawyers and staff in Moscow.

In the May 12 letter, Trump’s attorneys generally downplayed the president’s ties to Russia, and said Trump’s tax returns from the past decade contain no undisclosed income from Russian sources.

Murphy is correct that Morgan Lewis was once named the "Russia Law Firm of the Year." This award was bestowed in 2016 by Chambers & Partners, a reputable source of law firm rankings, which cited the firm’s work in Russia’s energy, finance and technology sectors.

Murphy’s spokesman, Chris Harris, also pointed us to an item on Morgan Lewis’ website trumpeting the accolade, calling it a "prestigious honor" that recognizes its Russia office’s excellence in client service, strategic growth and other achievements.

Elsewhere on Morgan Lewis’ website the firm boasts about its Moscow office, saying "Our lawyers are well known in the Russian market, and have deep familiarity with the local legislation, practices, and key players."

So what?

So Murphy is basically right on the facts: (1) Trump did use a letter from his Morgan Lewis tax attorneys to downplay Russia ties, (2) Morgan Lewis was named "Russia Law Firm of the Year," and (3) the firm has extensive Russia ties.

That said, it would be wrong to conclude that by hiring Morgan Lewis, Trump shares the firm’s extensive Russia ties. That’s unproven.

A Morgan Lewis spokesman told ABC News none of the firm’s attorneys have handled any business dealings for Trump in Russia. The spokesman added that Trump’s tax attorney, Sheri Dillon, has never been to Russia and does no work there.

The reality is, beyond a laugh line, there’s not much people should read into Murphy’s statement.

By the same logic, for instance, Trump’s tough talk toward Germany would potentially be undermined by the fact his tax attorneys work in a firm that operates an office in Frankfurt. And unless Murphy were willing to credit Trump for Morgan Lewis’ progressive telecommuting policy to help working parents, his position would lack coherence.

Our ruling

Murphy said, "Law firm @POTUS used to show he has no ties to Russia was named Russia Law Firm of the Year for their extensive ties to Russia. Unreal."

While any suggestion Trump shares the law firm's extensive ties is unproven, Murphy has the basic facts correct. The tax attorneys Trump has used to minimize his Russia ties are partners at Morgan Lewis, the 2016 "Russia Law Firm of the Year," which boasts significant work in Russia. The firm, however, says that Trump’s lawyer has done no work in Russia.

We rate Murphy’s statement Mostly True.