The Bundesliga has been warned that playing games behind closed doors could pose a public-health risk because fans will gather in front of stadiums.
The German football authorities are looking for a way to resume the 2019-20 campaign despite the ongoing coronavirus pandemic.
Bundesliga games could be underway again as early as mid-May, according to reports, though they will have to be played in empty stadiums for the time being.
But Jorg Radek, deputy chairman of the German Police Trade Union, says authorities are wrong to believe that banning supporters in the stands is enough to ensure public safety.
"Maybe it is possible to control what is happening in the stadium. This does not apply to the public space in front of it. The stadiums become a potential target for fans who want to support their team," Radek told Frankfurter Allgemeine Sonntagszeitung.
"That would be devastating. We can't have large crowds outside the stadium gates. It's not only forbidden, it would be irresponsible.
"It becomes relevant to the police at that moment, we then have to ensure that the requirements that currently apply to behavior in public space are complied with: the requirement of a distance of one and a half meters, the ban on the assembly of large groups, the wearing of masks.
"We will have to intervene in terms of maintaining security and order if this is not guaranteed.
"I want to state that we as a police union are not fundamentally against football games.
"I can also understand that there is a need for many people to stop watching old international matches or old Bundesliga games, but we must not forget what special situation we are all in - this includes the police.
"Games behind closed doors are a danger, even if the organiser does everything in the stadium to ensure that hygiene regulations are observed in order to keep the risk of infection as low as possible.
"It's a good right for the DFL to work out a plan to start again, but it doesn't seem to take all aspects into account."
Radek says police resources would struggle to cope with the extra demand should the German top-flight get back to business in the near future.
"It would be an additional burden for us," he added. "So far, we have been able to cope with our police presence in this pandemic situation so well because we have been relieved of such major events. Because there were no concerts, no demonstrations - and because sports, especially football, also ceased operations.
"Running the league on the weekends is a huge burden for us even without a corona pandemic. By pausing, we gained a personnel reserve that we could fall back on to increase our presence elsewhere."