In this Jan. 20, 2017, file photo, Donald Trump, Jr., and Ivanka Trump arrive on Capitol Hill in Washington.Saul Loeb/The Associated Press
The e-mail promised "very high-level" and "ultra-sensitive" information that would "incriminate" Hillary Clinton as part of a Russian government effort to support Donald Trump's bid for president.
Donald Trump Jr. quickly wrote back: "If it's what you say I love it."
The newly revealed correspondence from June, 2016, marks a striking development in the controversy over the Trump campaign's contacts – and possible collusion – with Russia to influence the U.S. presidential election.
Read Donald Trump Jr.'s e-mail chain about the meeting with the Russian lawyer
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The messages depict the junior Mr. Trump as an eager consumer of Russian information damaging to Ms. Clinton. The e-mail exchange and the meeting that followed could place him in legal jeopardy, some experts say. It is a federal crime to solicit or receive anything of value from a foreign national in connection with U.S. election campaigns.
Mr. Trump Jr. himself released the e-mails on Tuesday just as The New York Times was preparing to publish a story on their contents. His father issued a brief statement of support Tuesday via a spokesperson.
"My son is a high-quality person and I applaud his transparency," the President said.
The e-mail correspondence between Mr. Trump and Rob Goldstone, a British publicist with Russian business ties, culminated in a meeting at Trump Tower on June 9, 2016, with Natalia Veselnitskaya, a Russian lawyer. Also present at the meeting were Paul Manafort, then the campaign's top manager, and Jared Kushner, an adviser to the campaign and the President's son-in-law.
In a statement on Tuesday, Mr. Trump Jr., the President's eldest son, said he believed the information on offer was "opposition research" on Ms. Clinton. However, Ms. Veselnitskaya provided no such information at the meeting, he said, and instead wanted to discuss the Magnitsky Act, a bipartisan U.S. legislation enacted in 2012 that bars Russian officials suspected of human-rights violations from entering the country and freezes their assets.
Rick Hasen, an expert on election law who teaches at the University of California, Irvine, wrote Tuesday that after reading the younger Mr. Trump's e-mails, it is "hard to see how there is not a serious case" for a violation of campaign finance law, in particular its prohibition on soliciting anything of value from foreign nationals. "There's a lot for prosecutors to sink their teeth into."
Joseph Sandler, a specialist in election law who formerly served as general counsel of the Democratic National Committee, concurred. Tuesday's e-mails "greatly strengthened" the case that the younger Mr. Trump may have broken the law, he said, because they demonstrate he considered the information valuable and knew it came from a foreign national.
"It's surprising that there was this level of explicit encouragement of something clearly presented as a foreign government-sponsored effort to benefit the candidate," Mr. Sandler said. It is also astonishing, he added, that Mr. Manafort, the top official in the Trump campaign, would attend such a meeting. "What in the world would possess [Mr. Manafort] to meet with a Russian lawyer?" asked Mr. Sandler. One possible explanation: "They thought this was the Holy Grail here."
The e-mails are "extremely significant from a legal standpoint," said another expert in election law in Washington who spoke on condition of anonymity. "Subpoenas will be raining down on Trump Jr., Kushner, Manafort and Goldstone."
The fact that Mr. Goldstone described the information on offer as one part of an apparent broader effort by Russia to help the Trump campaign will also attract prosecutorial attention, the expert predicted. "That phrase 'part of' is going to be the subject of a lot of depositions," he said.
A lawyer representing the younger Mr. Trump did not immediately respond to a request for comment.
Discovering whether any laws have been broken will fall to Robert Mueller, the special counsel charged with investigating potential collusion between the Trump campaign and Russia. In recent weeks, Mr. Mueller has continued to add investigative firepower to his team, recruiting federal prosecutors with expertise in public corruption and international terrorism cases.
Members of Congress are conducting their own parallel probes into the Russia controversy. Both Republican and Democratic members of the Senate intelligence committee called this week for the younger Mr. Trump to testify. "Happy to work with the committee to pass on what I know," Mr. Trump Jr., 39, wrote on Twitter on Monday.
Mr. Trump Jr.'s version of what occurred has evolved. As recently as March, he told The New York Times he had never participated in any meetings involving Russian nationals where he was "representing the campaign in any way, shape or form."
In his initial statement regarding the June 9, 2016, meeting released on Saturday, he said the encounter primarily involved a discussion of an adoption program for Russian children (the program was ended in retaliation for the Magnitsky Act). On Sunday, he admitted the meeting was set up as an opportunity to receive information that would be "potentially helpful" for the Trump campaign in its battle against Ms. Clinton.
Mr. Goldstone, the publicist who brokered the meeting, originally reached out on behalf of Emin Agalarov, a Russian pop star and the son of Aras Agalarov, a Russian billionaire. The senior Mr. Agalarov partnered with the senior Mr. Trump to bring the 2013 Miss Universe pageant to Moscow. In his initial e-mail, Mr. Goldstone said Mr. Agalarov had met that morning with the "crown prosecutor" of Russia – an apparent reference to the country's top prosecutor – who offered to provide incriminating documents on Ms. Clinton.
Political consultants from both parties stressed how unusual the resulting meeting was. Matthew Dowd, a veteran of more than 100 campaigns who was chief strategist for George W. Bush's re-election bid, wrote on Twitter that it was the first time he had heard of someone meeting with a foreign adversary in order to get "oppo," or opposition research, on a competitor.
For Democratic lawmakers, the e-mails provided the first concrete evidence that the Trump campaign attempted to co-ordinate with elements in Russia to influence the election. "There is no longer a question of whether this campaign sought to collude with a hostile foreign power to subvert American democracy," said Senator Ron Wyden, who sits on the Senate intelligence committee, in a statement. "The question is how far the co-ordination goes."