Pennsylvania’s capital city, Harrisburg, filed for bankruptcy Tuesday—a move that surprised county commissioners, who plan to challenge the legality of such a proceeding. Harrisburg’s city council voted 4-3 to file the rare Chapter 9 motion—bankruptcy for municipalities—but already the county commissioners for the area and Harrisburg's mayor say the motion is illegal without the state’s permission. Harrisburg has listed debts of more than $400 million, $310 million of which comes from a failed incinerator project. The filing came just one week before the Pennsylvania House was set to consider a bill that would allow the state government to take over Harrisburg’s finances. While several other municipalities have filed for Chapter 9 in recent years, Harrisburg’s is one of the most high-profile and many wonder if this could be the start of a trend.