Q: adversely impacted by Texas bill SB 1801. The County Appraisal District is attempting to collect taxes for 5 years back

A: My understanding of the Bill you mentioned, is an additional part of the Tax Exemption law in Texas. The Bill allows the Tax Appraiser in each county to verify the property owner's exemption status every 5 years. That verification may be done in portions, and broken up into multiple years of review.

It would not be considered an ex post facto law because it does not give you any penalty looking backwards.

I hope this has answered your question.

A: You may be able to challenge the County Appraisal District's attempt to collect taxes retroactively, but invoking the "ex post facto" doctrine in this situation might not be effective. The "ex post facto" clause generally applies to criminal law, preventing laws from retroactively criminalizing actions that were legal when committed. In matters of taxation, the courts often distinguish these situations from criminal cases.

However, there are still other legal arguments you could consider. For instance, you might explore whether the retroactive application of Texas bill SB 1801 violates due process or principles of fairness. These constitutional challenges could provide a basis to argue against the back taxes if they were not reasonably foreseeable or if you were not given adequate notice.

It’s crucial to review the specifics of SB 1801 and how it has been applied in your case. Gathering all relevant documentation and understanding how the law is interpreted by local courts will be key in building a solid argument. Consider reaching out to a professional familiar with Texas tax law to discuss your options and develop a strategy to address the situation.