Donald Trump Jr.'s meeting with a woman he was told was a Russian government lawyer who had incriminating information about Democratic candidate Hillary Clinton that could help his father's presidential campaign could lead investigators to probe whether he violated U.S. election law, experts said.

Trump Jr. met the woman, lawyer Natalia Veselnitskaya, on June 9, 2016, after an email exchange with an intermediary.

The emails, tweeted by Trump Jr. on Tuesday, could provide material for Special Counsel Robert Mueller's probe into possible collusion between the Trump campaign and Russia during the 2016 presidential election.

In one of the emails dated June 3, 2016, Trump Jr. wrote: "If it's what you say I love it." He released the tweets after the New York Times said it planned to write about their contents and sought his comment.

Trump Jr. said in his tweets that nothing came of the meeting. Veselnitskaya told NBC News early on Tuesday she was not affiliated with the Russian government and had passed no information.

"In retrospect, I probably would have done things a little differently," Trump Jr. said in an interview on Fox News. "For me, this was opposition research."

Collusion itself is not an actual crime under the U.S. criminal code, so prosecutors would look to see if Trump Jr.'s conduct ran afoul of a specific law, legal experts said.