Christian Castro, 52, also faces state charges in the shooting.
A Hollywood movie producer was arrested this week after federal prosecutors in Illinois charged him with defrauding investors of more than $100 million in an alleged Ponzi scheme.
Lawyers with the DOJ have agreed to unilaterally withdraw a series of subpoenas that sought to compel New York Times journalists to testify about their sources.
The investigation is in part about his finances, sources told ABC News.
ECU is among five other medical schools being investigated by the Department of Education, the Department of Health and Human Services, and the Department of Justice.
A judge has referred President Trump's lawyers for potential disciplinary action for filing the suit against the IRS that led to the creation of Anti-Weaponization Fund.