TUCSON (CN) – Tucson and the state of Arizona are headed for a showdown in court over whether the city has the right to destroy confiscated guns, among other local-control issues.

In a recent lawsuit, the city maintains that the matter is the city’s business and the state should stay out of it. The move comes just days after state Attorney General Mark Brnovich asked the Arizona Supreme Court to cut off Tucson’s state funding because he says the city’s destruction of confiscated guns violates Arizona law.

On Dec. 6, the Tucson City Council voted unanimously to legally challenge the constitutionality of Senate Bill 1487, which was enacted this year to financially penalize cities for policies contrary to state statutes. An existing Arizona law backs the resale of firearms – but not their disposal.

The city has destroyed 4,820 firearms, most of them confiscated, although the Tucson Police Department also has disposed of guns that residents have turned in. The city has suspended the practice until the legal battle is resolved.

Tucson, which seeks to have the “coercive” SB 1487 declared invalid, maintains that its voter-approved city charter supersedes state law in local affairs.

In its Dec. 12 complaint, the city also takes to task an SB 1487 requirement that compels municipalities challenging the law to post a bond equal to half of the annual amount it gets in state funds.

“Posting a nearly $56 million bond would have catastrophic impact on the city, leaving it entirely vulnerable to economic variances,” the 30-page complaint reads.

The stakes are high for Tucson. The city stands to lose millions if the court sides with the state. The money derived from state-shared revenues generated through taxes on income, sales and transportation are a significant portion of local governments’ budgets. Tucson’s projected share in the current year exceeds $115 million – or 23.5 percent of the city’s general fund.

The state’s withholding of those funds would hurt Tucson’s law enforcement agencies, public transportation, and other city services. It could also lead to employee layoffs, city officials say in their complaint.

The Republican-controlled legislature passed SB 1487 in apparent response to Gov. Doug Ducey’s threats to take similar action during his State of the State address in January. Other Arizona cities also voiced opposition to the law before the governor signed it in March.

“In testimony before the House of Commerce Committee, [Senate] President [Andy] Biggs recognized that the threat of withholding shared revenue funds was a ‘stick’ to hold ‘over a recalcitrant municipality,’” the complaint states.

The law allows any state legislator to compel the attorney general to investigate local laws, regulations and policies that might clash with state laws. If a potential conflict exists and municipalities fail to come up with a resolution that satisfies the attorney general, the state will withhold funds, which will then be redistributed to other communities.

“SB 1487 empowers a single legislator and the attorney general to deprive the taxpayers and residents of Arizona cities of tax revenues that are dedicated and appropriated, by operation of statutes enacted through voter-approved initiative measures….this deprivation of tax revenues and the services they fund occurs without any prior action or even consideration by the Legislature and the Arizona courts,” city officials say.

The state’s attorney general said his office is reviewing the lawsuit.

Tucson’s city attorney was not available for comment.