A video of the two men at the polling place was widely distributed on the Internet, showing a man holding a police-style baton near the entrance to the polling place as voters filed in and out. The third man named in the case was the head of the group's local chapter, but was not present at the polling place.
Justice officials later chose to drop the matter against two of the men and get an injunction against a third. That prompted some conservatives to allege the three had gotten off lightly as a result of political interference from the new Democratic administration.
Justice Department officials have said the case was decided by career staffers, not political appointees, based solely on the facts and the relevant law.
The three had never responded to the government's lawsuit.
Now the department is conducting an inquiry into that decision, to be handled by the agency's ethics watchdog, the Office of Professional Responsibility.
The head of that office, Mary Patrice Brown, sent a letter to Rep. Lamar Smith, R-Texas, saying the matter was now being reviewed. The letter was dated Aug. 28 but only made public Wednesday.
Smith, the senior Republican on the House Judiciary Committee, praised Brown's move, saying the Justice Department's handling of the case "reeks of political interference."
Smith urged authorities to pursue the case against the three men "to the fullest extent of the law without political considerations."
