Grassley, Iowa's senior Republican senator, serves as chairman of the judiciary committee - one of several committees conducting investigations into possible coordination between the Trump campaign and Russian government to influence the 2016 presidential election.
The display showed Short talk to a music publisher who wanted to find a Russian government lawyer who would apparently take Clinton's dirt as 'part of Russian government support.
Sen. Richard Blumenthal, a member of the committee, said it was "long overdue" that Manafort be called to testify.
The Congressional investigation into Russia interference in the 2016 Presidential election was tensed on Wednesday after the legislators planned to question the former leader of the #trump campaign and decide whether the Russian social network trolls were involved in the short-term electoral efforts.
As part of its oversight of the Department of Justice, Grassley said the committee has an interest in learning more about whether the meeting violated the Foreign Agent Registration Act, which requires people representing foreign countries in a political capacity to disclose that relationship and information about related activities and finances.
April 12: Maloni announced Manafort meant to officially register as a foreign agent.
In a statement Tuesday, Trump's eldest son said he was posting the emails "in order to be totally transparent".
Grassley asks in his letter how Veselnitskaya and her colleagues were allowed to say almost six months after the expiration of her visa.
From the secretaries, Grassley requested "all visa records and associated documentation" for Veselnitskaya.
"If he [Manafort] comes before our committee, and we'll subpoena him if necessary", Grassley said.
A former assistant attorney general overseeing the criminal division under President George W. Bush, Wray now works as a criminal defense lawyer based in Washington, D.C.
The president's attorney, Jay Sekulow, said in an interview with NBC's "Today" that Trump Jr. did not violate any laws by accepting the meeting.
After the New York Times initially reported the meeting, Trump Jr. said that he believed he would be given opposition research against Clinton and maintained that he did nothing wrong or out of the ordinary.