Masked rioters have been identified by dropping their covers for smoke and drink breaks, a court heard.
Police disclosed the slip-up by offenders as they sought all media footage from an outbreak of violence in north Belfast this summer.
Lawyers for the Police Service of Northern Ireland want an order for full production of unbroadcast material and photographs taken during Twelfth of July disorder in the Ardoyne area.
The BBC, UTV, Sky News and the Press Association joined forces in resisting the application at Belfast Recorders Court.
Rioting erupted followed a contentious Orange Order parade and counter-demonstration by nationalist residents.
Twenty PSNI officers were injured and 17 shots were fired at police lines. Up to 90 people were involved in the trouble.
A detective sergeant in charge of the evidence gathering operation told the court more than 30 suspects have so far been arrested.
The court heard that film of the gunman was obtained from YouTube and aerially from a police helicopter.
It shows him emerging from the crowd, opening fire and then running back. He has not been identified.
The detective claimed unused material may hold evidential value, even though it was not regarded as newsworthy.