CONCORD, N.H. — A law allowing abortion clinics to create buffer zones of up to 25 feet is different from a Massachusetts law that was struck down last month by the U.S. Supreme Court and will survive a court challenge, New Hampshire’s attorney general said in legal filings.

In response to a lawsuit, Attorney General Joseph Foster argued in motions filed this week that New Hampshire’s law, which took effect July 10, provides for a flexible zone of up to 25 feet, not the strict 35 feet in the Massachusetts law. He also says zones would vary by location and may not be used at all at clinics where no problems exist.

“It does not mandate the creation of buffer zones,” the state argued.

The lawsuit seeks a preliminary injunction to keep the law from taking effect while a judge decides its constitutionality.

Backers said the law is needed to protect women and clinic staff from harassment while opponents, including the conservative group Alliance Defending Freedom, say the zones violate their right to free speech.

“Up to 25 feet” is one key to the state’s argument. It says courts have ruled that a buffer zone of, for example, 4 feet does not violate the First Amendment right to free speech.

Since the suit was filed, the state has agreed not to enforce it and Foster’s office argues that since it may never have to enforce it, the people who brought the lawsuit can’t prove any harm ”“ a key element in deciding whether to grant a preliminary injunction.

ADF, which brought the lawsuit and successfully sued to overturn the Massachusetts law, will argue in court that the flexibility of zones doesn’t mean they’re constitutional. In fact, ADF said, by ceding the decision to create zones to a private entity, the state undermines its own arguments.

“Narrow tailoring requires the government to show that banning speech is necessary to solve a problem instead of using other mechanisms,” ADF wrote in its motion. “Giving private parties the ability to suppress free speech does not remedy the (law’s) unconstitutionality, it exacerbates it ”“ especially when those parties are by definition hostile to a speaker’s message.”

Foster’s office also says the suit ought to be sent to state supreme court since it seeks to determine the constitutionality of a state law. ADF argues sending it to state court would be a needless waste of time and resources since it believes it will ultimately be ruled unconstitutional.

A hearing is set for Friday in U.S. District Court in Concord.