This is a good case of good men not doing what needs to be done. The locals certainly know which houses are drug houses.
Drug Prohibition is an illegitimate use of government power, it is not authorized by the US Constitution.
I don't understand why conservatives are so convinced to take over this failed liberal policy and make it their own. If you study the history of prohibition, you'll find that it is a liberal do-gooder policy to use the force of government power to mold people into their pre-determined form. Prohibition is the antithesis of conservativism.