Justin Bieber could be sent to federal prison and fined if the Federal Aviation Administration finds he interfered with the flight crew aboard a private jet, reports NBC News

Bieber and his father had been ‘extremely abusive’ to a flight attendant and would not stop smoking marijuana during a flight from Canada to New Jersey on Jan. 31.

FAA spokesman Jim Peters said Monday the agency’s Flight Standards District Office in Teterboro will do a ‘factfinding”’investigation with no specific timetable. He said the FAA will seek to determine if anyone on the flight violated the FAA regulation that states, ‘No person may assault, threaten, intimidate, or interfere with a crewmember.’

After the investigation is completed, said Peters, the Flight Standards unit will present its findings to the FAA’s legal counsel, who will decide whether to recommend prosecution. Should Bieber or any other passenger be charged and convicted, penalties are substantial.

Persons found to have violated the law ‘shall be fined.. imprisoned for not more than 20 years, or both.’ Fines for unruly passengers can reach $25,000 per violation, and ‘one incident can result in multiple violations.’