Washington (CNN) Sam Patten, the political consultant who last week was sentenced to three years probation on charges that stemmed from Robert Mueller's investigation, confronted a senior Justice Department official at a forum held by a Washington think tank Wednesday.

Speaking during the question and answer portion of a conference that centered on the foreign lobbying law that he admitted to violating, Patten introduced himself and presented a hypothetical situation that mirrored his own case to a panel that included John Demers, the assistant attorney general in charge of the Justice Department's National Security Division.

"My name is Sam Patten and I believe I'm the ninth conviction under FARA in American history, or at least post-war history," Patten said, referring to the Foreign Agents Registration Act -- the decades-old law that regulates foreign influence in the US.

Patten pleaded guilty last year to a criminal charge that he helped draft op-eds in US media for a Ukrainian oligarch ahead of an election there and arranged government meetings -- acts that he should have registered under FARA to carry out. On Wednesday, at the event hosted by the American Enterprise Institute, he pressed the panel with a question that appeared to apply elements of his own case to a hypothetical situation involving pro-Ukrainian opinion pieces issued by think tanks funded by political candidates in the country.

Application of the FARA law to non-profit organizations can be vague. Patten was accused of operating without the proper registration while working for a political consulting business he shared with a Russian also investigated by Mueller, Konstantin Kilimnik. Patten also admitted to using a straw purchaser to provide Trump inaugural tickets to Kilimnik and a Ukrainian oligarch, and he helped the Justice Department following his plea.

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