The U.S. Supreme Court’s decision Monday to let stand a ruling in an online defamation case will make it more difficult to determine correct legal jurisdictions in other Internet cases, legal experts said.

By opting not to take the case, the high court effectively endorsed a lower court’s decision that a Colorado company that posts ratings of health plans on the Internet could be sued for defamation in a Washington court. The lower court ruling is one of several that makes it easier for plaintiffs to sue Web site operators in their own jurisdictions, rather than where the operators maintain a physical presence.

The case involved a defamation suit filed by Chehalis, Wash.-based Northwest Healthcare Alliance against Lakewood, Colo.-based Healthgrades. com The Alliance sued in Washington federal court after Healthgrades. com posted a negative ranking of Northwest Healthcare’s home health services on the Internet. Healthgrades. com argued that it should not be subject to the jurisdiction of a court in Washington because its publishing operation is in Colorado.

Observers said the fact that the Supreme Court opted not to hear the case only clouds the legal situation for Web site operators.

Geoff Stewart, a partner at Jones Day in Washington, D. C. , said that the Supreme Court eventually must act on the issue, as Internet sites that rate everything from automobile dealerships to credit offers could scale back their offerings to avoid lawsuits originating numerous jurisdictions.

Online publishers also might have to worry about being dragged into lawsuits in foreign courts, said Dow Lohnes & Albertson attorney Jon Hart, who has represented the Online News Association.

"The much more difficult problems for U. S. media companies arise when claims are brought in foreign countries over content published in the United States," Hart said. Hart cited a recent case in which an Australian court ruled that Dow Jones must appear in a Victoria, Australia court to defend its publication of an article on the U. S.--based Walt Street Journal Web site.

According to Hart, the potential chilling effect of those sorts of jurisdictional decisions is substantial. "I have not yet seen publishers holding back on what they otherwise publish because they’re afraid they’re going to get sued in another country, but that doesn’t mean it won’t happen if we see a rash of U. S. libel cases against U. S. media companies being brought in foreign countries," he said.

Until the high court decides to weigh in directly on this issue, Web site operators that offer information and services to users located outside of their home states must deal with a thorny legal landscape, said John Morgan, a partner at Perkins Coie LLP and an expert in Internet law.

Geoff Steward maintains that the Supreme Court’s decision will make Internet companies（）

A. more liable to make negative ratings

B. more dubious about jurisdictions

C. more encouraged to launch defamations

D. more cautious in their offerings