Grassley noted he intends to question Manafort on the Foreign Agent Registration Act, including on his role in the meeting between Donald Trump Jr. and Russian lawyer Natalia Veselnitskaya in June 2016.
President Donald Trump's eldest son released an email chain Tuesday that shows him discussing plans to hear damaging information on Hillary Clinton that were described as "part of Russian Federation and its government's support for Mr. Trump".
Grassley said the committee would call Manafort to testify to learn why he didn't file as a foreign agent before becoming involved in the USA presidential campaign.
The activity also began before Manafort started working with the Trump campaign, the spokesman said.
He began the effort before the 2016 election - and his previous lobbying work was not conducted on behalf of the Russian government, the representative said.
Paul Manafort already has volunteered to talk to congressional intelligence committees investigating whether there was any collusion between the Trump campaign and the Russian government attempting to interfere in the 2016 presidential election.
Trump Jr. said Monday, after the meeting was reported but before releasing the emails, that he is "Happy to work with" another Senate committee "to pass on what I know".
Chairman of the Senate Judiciary Committee Chuck Grassley in Washington on September 20, 2016.
The heads of the Senate judiciary committee are writing a letter to Donald Trump Jr.
In the emails, Trump Jr. was told by an interlocutor that he could get "very high level and sensitive information" that was "part of Russian Federation and its government's support for Mr. Trump".
Grassley said there will be a hearing within days on the lax enforcement.
The Iowa Republican told reporters he thinks there has been "lackadaisical enforcement" by the Trump and Obama administrations.
However, Veselnitskaya was able to come into the United States, after requesting a meeting with Donald Trump Jr. through an intermediary promising damaging information on political opponent Hillary Clinton. He was told the Russian government had information that could "incriminate" Clinton and her dealings with Russia.
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.
Third-Party Contractor Exposes Verizon Customer Data
In the RNC leak, UpGuard found an online repository of voter information left unsecured on Amazon Web Services' servers. Verizon has disputed this number; according to a company spokesperson there were 6 million records in the data.
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