Pub 17

Deductible real estate taxes are any state, local, or foreign taxes on real property
   levied for the general public welfare. The taxes must be based on the assessed
   value of the real property and must be charged uniformly against all property under
   the jurisdiction of the taxing authority. Deductible real estate taxes generally do not
   include taxes charged for local benefits and improvements that increase the value of
   the property.