COST - Council on State Taxation

Amicus Briefs

AT&T Mobility, LLC v. Board of Supervisors of Lamar County, Mississippi

COST filed an amicus brief requesting the Supreme Court of Mississippi to accept an interlocutory appeal to address both the legality of, and constitutional issues with, a county assessor’s property tax valuation of a telecommunications company’s personal property. The brief pointed out concerns with the assessor not following the State’s valuation process which for industrial personal property is

COST - Council on State Taxation

COST Studies, Articles & Reports

2026 State and Local Amnesty Programs

Tracker of most state and local tax amnesty programs enacted and conducted in 2026.

COST - Council on State Taxation

COST Comments & Testimony

Coalition Letter in Opposition to Certain Revenue Raisers in Governor's Budget

COST joined CalTax in opposing a number of revenue raising proposals included in Governor Newsom’s 2026 May Budget Revision. The proposals include the taxation of downloaded software and the capping of business credits.