News broke on Wednesday that FBI agents had quietly raided former Trump campaign chairman Paul Manafort's home in late July, just one day after he testified before the Senate Intelligence Committee.

Their search warrant was related to special counsel Robert Mueller's investigation into allegations the Trump campaign colluded with the Russian government during last year's election cycle. After he took the helm of Trump's campaign in June of 2016, a job he remained in only until August, Manafort's lobbying career went under the microscope. He resigned from the campaign after the Associated Press reported that he worked with the Ukrainian government to route millions of dollars in payments to two Washington lobbying firms in 2012.

In doing this, however, Manafort had failed to register as a foreign agent for his work on behalf of these pro-Russian forces in Ukraine. He belatedly did so in June 2017, although the law requires registration occur within ten days after entering into an agreement to represent a foreign power.

It wasn't until this July that we learned Manafort was some $17 million in debt to companies tied to a Russian oligarch, tied to Vladimir Putin, and tied to a pro-Putin Ukrainian politician.

As we observed in an editorial earlier this year, Manafort was "likely" behind the Republican Party's removal of language calling on the U.S. to arm Ukraine "with lethal defensive weapons" against Russian invaders from its platform in 2016.

Manafort was also present for the meeting with a Russian lawyer Donald Trump Jr. revealed he took in order to obtain opposition research on Hillary Clinton during the heat of the campaign.

Manafort's lobbying ties are convoluted but appear increasingly relevant to the special counsel's investigation into whether the Trump campaign colluded with Russia.

Emily Jashinsky is a commentary writer for the Washington Examiner.