"However, a 2003 IRS chief counsel memorandum said, "Mello-Roos and other California assessments may be deductible as real property taxes, even though they are not imposed upon an 'ad valorem' basis."
*In December, the tax board wrote to the IRS asking it to clarify its position.
In a letter dated Feb. 6, an IRS associate chief counsel said the Internal Revenue code does not explicitly say real estate taxes must be ad valorem to be deductible. It says taxes that are not ad valorem could be deductible "if they are levied for the general public welfare by a proper taxing authority at a like rate on owners of all properties in the taxing authority's jurisdiction, and if the assessments are not for local benefits (unless for maintenance or interest charges)."*
It doesn't get much clearer than that....