Originally published Thursday, January 10, 2019 at 07:24p.m.

PHOENIX – State revenue officials are preparing new tax forms with yet-to-be-approved changes in the law sought by Gov. Doug Ducey that will take an additional $180 million or more out of the pockets of Arizonans even though the Legislature has not given its approval.

In an announcement on the agency's website Thursday, the Department of Revenue acknowledges the forms and instructions it is crafting are based on the presumption that lawmakers will agree to “conform” Arizona tax laws to changes made by Congress in the Internal Revenue Code. The agency is moving now to ensure forms will be available both online and in paper by Jan. 28, the first day federal tax forms can be filed.

On one hand the move is not surprising. State officials are empowered to act in similar fashion every year while awaiting legislative action to adjust the state tax code to match federal law, a move designed to make filing of state forms simpler.

House Speaker J.D. Mesnard said this isn’t some simple tweak, citing figures from legislative and revenue staffers that show following federal suit will mean a big boost in what some state residents owe. Mesnard, who is moving to the Senate and will chair the Finance Committee when the session begins Monday, said he will fight Ducey’s effort as an unfair “windfall” for the state at the expense of Arizona taxpayers.

What that means is those who use these new forms do so at their own risk. If lawmakers balk at Ducey’s plan, they could end up having to file amended returns.

In fact, Mesnard is suggesting the best course of action for Arizona taxpayers is to seek an automatic extension from the April 15 filing date, waiting to see what is finally approved.