BALTIMORE (AP) — Baltimore officials will appeal a federal judge’s ruling that part of their package of pension reforms to for police officers and firefighters is unconstitutional.

Lawyers for the city have filed a notice of appeal with the 4th U.S. Circuit Court of Appeals in Richmond, Va.

At issue is the city’s plan to replace a variable benefit tied to the stock market with a fixed cost-of-living adjustment. Under the current system, retired police officers and firefighters get a bump in their pension benefits when the stock market goes up. City officials say that causes a drain on the fund when the market tanks.

The city wants to implement a system of cost-of-living increases based on age. A judge sided with unions for police and firefighters in ruling that change was discriminatory.

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