I get it that bad guys are welcomed in churches, supposedly so they can be convinced to repent- which means, don't continue to do the bad thing anymore. People in churches usually want to give bad guys a chance to stop being bad guys, and I can respect that.
But what if the bad guys don't even admit they are doing anything wrong?
Would your church allow an unrepentant murderer to attend without calling him out on it? Without demanding he turn from his ways and atone? Probably even insisting that he accept the painful and unpleasant consequences for his actions?
Would a church just let a rapist who admits he has non-voluntary sex with people on a daily basis, but who denies he's doing anything wrong by doing so (perhaps rejecting the label of "rape" for his actions), keep sitting among the members? Sunday after Sunday, without calling him aside about what he continues to do?
If your church allows cops to attend, without insisting they turn from their ways and stop being a cop, it is doing the exact same thing. If they attend church in uniform, it's even worse. In this case they are celebrating and advertising what they do. Probably even being prideful about it. And delusional church members may even believe they are doing a good thing!
But there are no good cops, and good people can't support cops without compromising away their good. It doesn't change matters if you are sitting in a pew, or standing behind a pulpit. If you condone what cops do, you have no moral high ground from which to speak to anyone about moral matters. You are an empty shell.
If I attended church I couldn't continue to attend one that didn't ask cops who showed up for services to turn from their ways. Relentlessly, until they change "jobs" or stop attending. My dislike for hypocrisy and inconsistency just wouldn't let me stay.