Your thoughts?

Poll taxes were one such punitive tax. So was the tax on printer's ink that was struck down by SCOTUS in Minneapolis Star & Tribune Co. v. Minnesota Commissioner of Revenue, 1983.

http://law.jrank.org/pages/12734/Minneapolis-Star-v-Minnesota-Commissioner-Revenue.html

Washington has state preemption concerning firearm laws. Seattle simple did not have the right to pass the so-called "gun violence tax."

It doesn't matter if the law passed unanimously, is supported by all of Seattle, is only a minor financial inconvenience, and is the best darn gun law ever devised by the imperfect hand of man, it will still be struck down because the city did not have authority to enact such a law.

If Seattle wants a "gun violence tax," they need to convince the state legislature and governor (although if such a law passed, it would indeed be challenged on constitutional grounds).

They squall mightily if some speak of not complying with registration and confiscation laws. Yet, they feel no compunction to abide by laws that deny them the ability to infringe upon the rights of others.

of shifting ammunition and firearm sales to just over the city line.

Not a single gun store in the entire city and only 3 or 4 left in Cook County.

It's not about "recovering the money" it's about making it harder for poor people to exercise their 2nd amendment rights.

just like Chicago, they will also involuntarily donate substantial funds to gun rights groups to lobby and challenge more gun control laws.

but is there any civil liability on the city for lost business if/when the law is overturned? does the city enjoy some sort of immunity or is there a very high burden of proof upon the plaintiff?

law, and overall the matter is somewhat complicated.

Disclaimers aside, the city would not have immunity to a federal civil rights action or against a declaration that it violated state law. In this instance, the city will need to bear a high burden of proof either to demonstrate the tax is constitutional or that it is not preempted. The exact level of scrutiny of any constitutional analysis is an evolving area of law, and I don't know the level of deference given to local ordinances in Washington state local/state conflict of law jurisprudence. Any limitations of damages for breach of state law would be determined by Washington state law.

If the plaintiffs prevail in a civil rights cause of action, they are generally entitled to recover provable direct damages and legal fees. It's doubtful that plaintiffs like the NRA and SAF actually suffered any damages, and given that the law just passed (I don't know if it is yet effective or if the plaintiffs have or will seek an injunction), the damages suffered by the retail plaintiffs would be similarly de minimus. I'm uncertain about the result if a Washington state court strikes the city ordinance as violating state preemption without reaching the constitutional issue at all or if state law explicitly provides for legal fees or statutory damages.