Now that you are getting interested in finding out how your local sheriff and police stand on the second amendment, If they are supporting it, don't leave them out on a limb. The one stick that Washington DC has is funding. Ask your city commission or county commissioners about how much DC funds your local law enforcement (with our own money). The most important thing today, is to make local law enforcement independent of federal funds. I know how all you conservatives and libertarians detest taxes, but is best if local law enforcement is funded entirely out of local taxes and has no dependence on Washington. Don't let them accept federal funding; that just puts them under federal control. If you have to, put forth petitions for local tax increases earmarked for law enforcement. Make these increases contingent on not accepting federal largess. Make sure the local law enforcement know you are trying to help them and keep them independent.
However, if they take positions violating the Second Amendment, then there are always elections. Make sure they know that also. If you can find a candidate that really drives home these problems, then support that or those candidate(s) with money and other grass roots support. Make sure your congress critter and senators know what you are doing. Don't depend on any political party for anything.