The new tax bill (Federal, United States) allows only a $10,000 deduction for 2018 for state income tax plus real estate tax. There was considerable backing and forthing on this as the tax bill neared completion, but that was the final result.
Then, just as myriads of home owners prepared to prepay their 2018 real estate taxes, the IRS (if I remember correctly) said, no you can't do that. More backing and forthing. Then the ruling was that you could prepay real estate taxes if the jurisdiction in which you lived allowed you to do so. So now it was not a federal decision, or, in some cases, not even a state decision. People scrambled to find out what their county allowed, and many column inches were published in the Washington Post (WP) explaining what was what for Maryland, Virginia and the District.
We had sent off our check before the not-so-final word was reported in the WP, and, guess what? Our county, in a state that did not allow prepayment, cashed our check and recorded the first (of two) payments for 2018 as paid. Naturally, we took the deduction on our 2017 return.
My question is: What did the IRS finally decide to do? Enforce the rule (see bolded sentence above). or decide it was a low priority and/or too much work to enforce?