The Dallas Cowboys’ plan to wear helmet decals honoring the city’s five slain police officers during preseason and regular-season games has been turned down by the NFL.

“Everyone has to be uniform with the league and the other 31 teams,” Stephen Jones, the team’s executive vice-president, said Wednesday (via the Dallas Morning News). “We respect their decision.”

The team can wear the decals, which include a five-pointed star and the words “Arm in Arm,” during training camp practices, though.

“There are so many wonderful, wonderful causes, the league has to be careful,” Jones said earlier of the possibility that the decals might not be approved. “If you allow one, then what do you do about every team that has a great reason to have something on their helmets?

“There are tons of things out there that need to be recognized. Once you open that Pandora’s box, how do you ever stop?”

Tight end Jason Witten was one of the forces behind the decal, which was unveiled at the first practice July 30 when players, coaches and executives walked onto the practice field arm-in-arm with Dallas Police Chief David Brown, Dallas Mayor Mike Rawlings and family members of the officers who were shot to death in July.