Sinn Fein councillors in Strabane have been unable to fill their positions on the area's District Policing Partnership.
DPPs monitor the effectiveness of policing in their areas
The party was entitled to five places, but could only find three candidates willing to take part.
The two spare posts were offered to DUP councillors hours before the deadline for nominations expired on Tuesday.
The inability to fill the positions followed weeks of internal wrangling within Sinn Fein.
Sinn Fein West Tyrone MP Pat Doherty said he was disappointed the party's group on Strabane District Council did not to reach agreement on its full complement.
"Sinn Fein is fully committed to engaging with all of the policing structures," he said.
"I am confident that right across the north we will continue to provide constructive leadership in ensuring accountable policing that serves people in the communities we represent."