Arlington County police have decided not to charge Patrick Moran in connection with possible voter fraud, authorities announced Thursday.

Arlington police and prosecutors initiated an investigation following an undercover video that was released in October showing Moran discussing possible voter fraud with an activist posing as a campaign worker.

Authorities have closed their investigation, saying the person responsible for making the video was uncooperative. They also noted that Moran and the Jim Moran for Congress campaign provided “full cooperation.”

Moran, the son of 11-term Rep. James P. Moran Jr., resigned from his father’s campaign shortly after the video was released.

In the video, dated Oct. 8 and posted by conservative activist James O’Keefe, Patrick Moran does not explicitly advocate or condone the worker’s suggestion to cast ballots on behalf of 100 voters he says are unlikely to show up Nov. 6.

Moran, who appears not to know that he is being recorded, attempts to discourage the worker from carrying out the scheme, saying he should instead join get-out-the-vote efforts. But Moran, who was then a campaign field director, also offers guidance on how to possibly skirt Virginia’s new voter identification laws. He also doesn’t tell the worker not to proceed with his plan.

Patrick Moran ran into additional trouble in December, when he pleaded guilty to assaulting his girlfriend, admitting to a role in an alcohol-fueled incident outside a Northwest Washington night spot.