WASHINGTON — The Justice Department told a lawmaker this week that it had stopped defending a federal prohibition on female genital mutilation because of flaws in the law, two weeks after it also began fighting the Affordable Care Act in court rather than defend it.
The department “reluctantly determined” that it could not appeal a federal judge’s decision to throw out a female circumcision case because the statute outlawing the practice needed to be rewritten, the solicitor general, Noel J. Francisco, wrote in a letter to Senator Dianne Feinstein of California, the top Democrat on the Senate Judiciary Committee.
The decision by law enforcement officials to step back from advocating two statutes is highly unusual. Defending laws on the books is a principal function of the Justice Department, and only about once a decade since World War II has it declined to support a law enacted by Congress, according to Walter E. Dellinger III, who served as the solicitor general during the Clinton administration.
While there are important differences between the two cases — Republicans have attacked the Affordable Care Act in the courts for years, while legal experts are debating whether the circumcision law is defensible — critics were troubled by what they fear is an emerging view inside the Justice Department that it is up to the Trump administration, not members of Congress, to decide whether a law has merit and should be enforced.
“Imagine a world where an administration of one party passes a law and then a different president effectively invalidates it by having the Justice Department refuse to defend it in court,” said Joshua Geltzer, the executive director of the Institute for Constitutional Advocacy and Protection at Georgetown Law School.
“You want elected lawmakers to draft laws, not lawyers at the Justice Department,” Mr. Geltzer said.
In 1996, Congress outlawed female circumcision on minors, except in cases where the operation is medically necessary. The statute was tested for the first time last year when federal prosecutors charged four mothers who brought their daughters to a clinic in Livonia, Mich., and had them circumcised. Doctors and others involved in the procedures were also charged.
The government presented evidence that the defendants contributed to mutilating nine children in their care, but a Federal District Court judge threw out the case, citing flaws in the law that he said made it impossible to find the defendants guilty.
The Justice Department declined to pursue an appeal as it typically would, Mr. Francisco wrote, because Supreme Court rulings handed down after the law was passed prevented the government from mounting “a reasonable defense of the provision, as currently worded.”
Mr. Francisco’s letter came on the heels of the Justice Department’s request in March that an appeals court validate a December ruling by Judge Reed O’Connor of Federal District Court in Fort Worth, Tex., that struck down the Affordable Care Act on the grounds that its mandate requiring people to buy health insurance was unconstitutional.
Democrats quickly condemned the Texas ruling, which jeopardized the health coverage of millions of Americans, and it prompted debate as well among legal scholars across the spectrum, who disagreed as to whether an entire law must fall if one part of it is flawed.
The decision to urge the appeals court to side with Judge O’Connor was controversial inside the Justice Department as well. Only political appointees and a lawyer on a brief loan to the Securities and Exchange Commission signed the letter to the appeals court, not career department lawyers who are experts on the health care law.
The Justice Department generally defends any federal statute if a reasonable argument can be made in court that it is lawful. That position ensures that the department and the executive branch cannot usurp Congress’s lawmaking powers by defending only certain laws.
Department lawyers often have informal discussions with lawmakers and their aides about language they believe could strengthen a law, particularly when Congress first considers a bill or after a Supreme Court ruling changes the judicial landscape and has an effect on existing legislation. Such a ruling affected the law prohibiting female genital mutilation.
In drafting that law, Congress relied on its power to regulate interstate commerce. Lawmakers had increasingly used that authority to overcome the fact that they cannot simply make local crimes federal matters, no matter how evil, unless they violate some federal power that Congress wields.
“For this to work, Congress has to show that there is some connection between the criminal conduct and interstate commerce,” said Mr. Dellinger, now a partner at the O’Melveny & Myers law firm.
But in 2000, four years after the female circumcision law was enacted, the Supreme Court examined Congress’s use of the Interstate Commerce Act in drafting the Violence Against Women Act. In that case, United States v. Morrison, the government lost in part because the court had greatly narrowed Congress’s ability to use its power over interstate commerce to draft criminal laws.
Last year, in the first court case involving the genital mutilation law, the judge in Michigan cited the Morrison case to rule that Congress had failed to clearly draw a connection between interstate commerce and the practice of female genital mutilation.
In his letter to Ms. Feinstein, Mr. Francisco sent a list of possible changes to the law to strengthen the connection with interstate commerce and keep the ban on female circumcisions in place, like outlawing the use of the banking or telecommunications systems to perform the act.
“Essentially, the Justice Department is urging Congress to fix the law before a case gets to the Supreme Court, where there is a good chance it would be struck down,” Mr. Dellinger said, adding that the government’s action in this case was appropriate. “The constitutional fix is relatively straightforward, and should be uncontroversial.”
Mr. Geltzer called on the department to present fixes to Congress while defending the law in court rather than set it aside completely.
“Lawyers at the Justice Department often find that a law could have been written more clearly,” he said, “but it’s rare that one is written so poorly as to be completely indefensible.”