COOK COUNTY, Ill. - When is a cigarette not a cigarette? That??s what two tobacco industry trade groups have filed suit to find out. A lawsuit filed by the Cigar Association of America, the National Association of Tobacco Outlets and Arango Cigar Co. seeks clarification on what constitutes a cigarette after Illinois changed its cigarette tax law last month, the Chicago Sun Times reports.

The lawsuit alleges that the new tax offers a "unconstitutionally vague" definition of cigarette that could trigger seizure of products if storeowners guess wrong. Retailers could also accidentally cause some buyers to overpay because of tax stamp mistakes.

The new law raises the cigarette tax by a $1 per pack and also hiked taxes on roll-your-own cigarettes, little cigars and moist snuff from 18% to 36% of the product??s cost. Retailers have until August 1 to comply with the changes.

The lawsuit wants an injunction that halts the changes and stops the state from enforcing the new law in retail stores.