The Supreme Court wrangled on Wednesday over the question of whether a disability rights activist could sue a hotel for violating a federal disability law, even if she never planned to stay there.

Several justices appeared skeptical of the case itself and whether there was even a dispute to resolve.

“This is like dead, dead, dead, in all the ways something can be dead,” Justice Elena Kagan said during an argument that lasted about an hour and a half. “To use that case as the vehicle for deciding an important issue, an issue that probably is going to need to be decided at some point but surely could come up in a live case, I guess it just doesn’t seem like something that a court should be anxious to do.”

The activist, Deborah Laufer, a Florida woman diagnosed with multiple sclerosis, had sued an inn on the southern coast of Maine, claiming it violated the Americans with Disabilities Act, a civil rights law that requires hotels to disclose accessibility information.

Ms. Laufer is what is known as a “tester,” a self-appointed person who challenges companies over violations of the act. According to court papers, she has filed more than 600 lawsuits over the issue. Such challenges typically demand that a company admit it broke the law and then fix the issue, as well as pay legal fees.

At issue is whether such testers can force businesses to comply with the American with Disabilities Act even if they never planned to visit the business. Although the question presented is narrow, the decision could have broader repercussions for other types of tester cases, including those involving housing discrimination.

However, Ms. Laufer has asked the court to dismiss the case. The hotel is now under new ownership, and its website has been updated to reflect disability accommodations.

After Justice Kagan expressed skepticism that the court should dedicate more resources to a case that is no longer in dispute, Adam G. Unikowsky, the lawyer for the hotel, pushed back.

If the court did not decide this case, he said, the same situation would repeatedly emerge in lower federal courts. That prompted Justice Ketanji Brown Jackson to suggest that perhaps the court could “just wait until it comes up again.”

A lawyer for the government echoed that approach, arguing the case was moot.

“We have not only a plaintiff who no longer seeks to litigate her claims, a defendant who no longer owns the hotel but also a website that is no longer lacking the relevant information,” said Erica L. Ross, an assistant to the solicitor general.

Chief Justice John G. Roberts Jr., however, expressed skepticism about the tactics Ms. Laufer had used.

If the court dropped the case, he said, “it doesn’t stop any of the other dozens of people, however many there are, who are doing the same thing.”

Several of the justices focused on hypotheticals aimed at understanding parallels between Ms. Laufer’s actions as a disability tester and a well-known Supreme Court decision in 1982 involving Black testers.

In that case, Havens Realty Corp. v. Coleman, the court upheld a broad definition of who could sue landlords for violations of the Fair Housing Act of 1968, based on a case in which a white and a Black tester answered an advertisement about apartments. The Black woman was told there were no vacancies, while the white man was told apartments were available.

Justice Jackson raised an analogy to Black people who challenged segregated lunch counters and asked whether Ms. Laufer was experiencing such discrimination when she looked to see if hotels explained their accessibility.

“They’re not actually there for the sandwich,” Justice Jackson said. “They’re going in because they are putting themselves into a discriminatory situation in order to be able to challenge the policy.”

Justice Jackson questioned whether Ms. Laufer’s situation was similar.

“Is she really experiencing discrimination?” she said. “Is that what we’re supposed to be kind of thinking about?”

If the justices rule broadly and decide that testers cannot bring such lawsuits, it could have serious consequences, according to legal experts and housing advocates.

“The implications are profound,” said Morgan Williams, general counsel for the National Fair Housing Alliance, a nonprofit focused on compliance and enforcement of fair housing laws. “The holding could be fundamentally destructive to what we do to enforce the Fair Housing Act.”

The case, Acheson Hotels v. Laufer, No. 22-429, started in September 2020, when Ms. Laufer sued Acheson Hotels, the operator of the Coast Village Inn and Cottages, a small hotel in Wells, Maine.

In the lawsuit, Ms. Laufer, who uses a wheelchair, accused the Coast Village Inn and Cottages of violating federal regulations that require hotels to disclose information about accessible rooms on their websites.

In her complaint, Ms. Laufer said she did not plan to stay at the Maine hotel but rather that she was a tester, someone who investigates whether hotels comply with federal disability laws. She asked the federal court to order the hotel to change its online reservation system to comply with the Americans with Disabilities Act and to pay legal fees.

Ms. Laufer later amended her lawsuit to say she also planned to drive from Florida to Maine to meet her sister and accompany her granddaughter to various stops, including tourist attractions. By omitting information about accommodations for people with disabilities, she argued, the hotel had infringed on her “right to travel free of discrimination.”

The district court dismissed her case, finding that she lacked the right to make a legal claim, a legal term known as standing. It was “implausible” that Ms. Laufer planned to visit Maine, the judge wrote, adding that she could not show “concrete harm.”

The U.S. Court of Appeals for the First Circuit, based in Boston, reversed that decision, pointing to the 1982 ruling from the Supreme Court.

The hotel asked the Supreme Court to take the case and questioned Ms. Laufer’s motives in bringing the lawsuit.

In their petition, lawyers for the hotel called the case one of “immense practical importance” and added that Ms. Laufer was one of many testers who “have collectively brought thousands of lawsuits under the A.D.A.”

“A cottage industry has arisen in which uninjured plaintiffs lob A.D.A. lawsuits of questionable merit, while using the threat of attorney’s fees to extract settlement payments,” the lawyers wrote. “These lawsuits have burdened small businesses, clogged the judicial system and undermined the executive branch’s exclusive authority to enforce federal law.”

In July, lawyers for Ms. Laufer had asked the court to dismiss the case as moot. They said she had voluntarily dropped her case against the hotel after a lawyer representing her was disciplined by a federal court in Maryland.

Lawyers for the hotel asked the court to move forward with the case, and the justices, in an unsigned order, agreed. They noted that the issue of whether the case was moot could be considered during oral arguments.