SAN FRANCISCO » Yelp.com is warning that a California lawsuit targeting critical posts about a law firm could lead to the removal of negative reviews and leave consumers with a skewed assessment of restaurants and other businesses.

Lawyer Dawn Hassell said the business review website is exaggerating the stakes of her legal effort, which aims only to remove from Yelp lies, not just negative statements, that damaged the reputation of her law firm.

Though its impact is in dispute, the case is getting attention from some of the biggest Internet companies in the world, which say a ruling against Yelp could stifle free speech online and effectively gut other websites whose main function is offering consumers reviews of services and businesses.

A San Francisco judge determined the posts were defamatory and ordered the company to remove them two years ago, which a second judge and a state appeals court upheld.

Yelp is asking the state Supreme Court to overturn the order. The high court faces an Oct. 14 deadline to decide whether to hear the case or let the lower-court ruling stand. Experts expect Yelp to prevail.

“There were a lot of people who were unhappy about this opinion,” said Eric Goldman, co-director of the High Tech Law Institute at Santa Clara University School of Law.

Internet giants Facebook, Twitter and Microsoft said in a letter to the California Supreme Court last month that the ruling “radically departs from a large, unanimous and settled body of federal and state court precedent” and could be used to “silence a vast quantity of protected and important speech.”

Yelp said it would give businesses unhappy about negative reviews a new legal pathway for getting them removed. They could sue the person who posted the content and then get a court order demanding the Internet company remove it.

But Hassell disputes the ruling would do anything that drastic.

Her 2013 lawsuit accused a client she briefly represented in a personal injury case of defaming her on Yelp by falsely claiming that her firm failed to communicate with the client, among other things.

San Francisco Superior Court Judge Donald Sullivan ordered the client and Yelp to remove the statements. Hassell said the client failed to answer her lawsuit or remove the posts, so she had to seek a court order demanding that Yelp do it.

“We have an impeccable reputation,” she said of her firm, Hassell Law Group. “We have a right to protect it.”

Yelp says the judge’s order violates a 1996 federal law that courts have widely interpreted as protecting Internet companies from liability for posts by third-party users.

A federal appeals court cited the law in a Monday ruling saying Yelp’s star rating system did not make it responsible for a negative review of a Washington state locksmith business because the overall rating is based on user reviews.

In Hassell’s case, a three-judge appeals panel has said the order requiring Yelp to remove the defamatory statements did not violate the 1996 Communications Decency Act because the company was not facing liability. That’s because Hassell’s lawsuit named her former client and not Yelp, the appellate court said.

The review site says the law is broader and prevents the courts from treating the company as the speaker or publisher of users’ posts regardless of whether it’s named in a lawsuit.

The ruling “would really inhibit a website’s ability to provide a balanced spectrum of views online and make it more doubtful that people would get the information they need to make informed decisions,” said Aaron Schur, Yelp’s senior director of litigation.

Yelp uses an algorithm to weed out biased and malicious reviews and encourages users to contact the company if they receive a final determination from a court that a review is defamatory.

In Hassell’s case, Yelp has questioned the court’s finding that the posts were defamatory.

Hassell said her lawsuit will not affect negative reviews on Yelp. She said she was the victim of lies and spent a considerable amount of effort and money to get a court to rule that the former client’s comments were defamatory.

“You can give critical reviews about people on the Internet,” she said. “It doesn’t mean it’s going to be defamation. You can’t write untruthful content to hurt somebody.”

Goldman of the Santa Clara University School of Law didn’t think the courts treated Hassell differently because her business is a law firm, as opposed to a restaurant or other business in the service industry.

Daphne Keller, an Internet law expert at Stanford Law School and former attorney at Google, said prior court decisions favor Yelp and she would be surprised if the California Supreme Court didn’t reverse the ruling.

“It should be a no-brainer for Yelp to win,” she said.