WELL BEFORE D.C. voters gave overwhelming approval to a referendum backing local budget autonomy, there was disagreement about the legality of the effort to free the District’s finances from Congress. The city’s attorney general argued against putting it on the ballot, the D.C. Council had its own counsel attesting to its soundness, and the mayor went along despite some doubts. So the current standoff over implementation of the referendum was clearly foreordained; the only way it can be resolved now is with a court deciding which side is right.

One branch of government suing another is not something we generally cheer, but the D.C. Council has no choice but to go to court to seek clarity on the validity of the local Budget Autonomy Act. The measure allowing the city to spend locally raised tax revenue without a separate annual congressional appropriation was passed by the council, signed by Mayor Vincent C. Gray (D) and ratified by 83 percent of voters last year. It became law in July after Congress took no action, but its legality was questioned by Attorney General Irvin B. Nathan and in a nonbinding opinion by the Government Accountability Office, Congress’s investigative arm.

Last week, Mr. Gray and Chief Financial Officer Jeffrey S. DeWitt said they would not implement any budget adopted under the act, citing Mr. Nathan’s judgment that the statute is invalid. The council has retained pro-bono counsel who are expected to file suit as early as Thursday in D.C. Superior Court seeking to compel the mayor and Mr. DeWitt to enforce the law. Speedy action will be needed, since the council is set to act next month on the fiscal 2015 budget. Karen L. Dunn, a partner with Boies Schiller & Flexner LLP, and Brian D. Netter, a partner with Mayer Brown LLP, told us that they researched the issue with an open mind and that consultations with numerous legal scholars and experts convinced them of the validity of the law. They said previous analysis failed to take into account precedents based in federal budget laws that buttress the city’s ability to control its own money.

We hope their assessment prevails in court. Because what is not in dispute — by Mr. Nathan or Mr. DeWitt or Mr. Gray or leading members of Congress or the president of the United States — is that the District should have the ability enjoyed by every other local jurisdiction to spend its locally raised tax dollars without approval or interference from Capitol Hill.