The justices also let stand a government rule forbidding Visa and MasterCard from restricting its member banks from also issuing credit cards by rivals American Express and Discover.
The high court turned away nearly 1,800 appeals in all, many of them arising out of California legal disputes, including:
. Tribal gaming. The court ignored an appeal by a group of San Francisco Bay Area card clubs and charity groups, which had challenged a state law that they claimed gave Indian tribes an illegal monopoly in casino-style gambling.
. Gun sales. The court upheld the right of California cities and counties to prohibit gun sales on fairgrounds and other public property. Los Angeles County had adopted such a law to ban firearm sales at the county fairgrounds in Pomona, triggering a lawsuit by gun promoters.
. Contraceptives. The justices rebuffed a legal challenge to a state law requiring employers, including those linked to the Catholic Church, to include contraceptives as part of their prescription drug benefit.
In the "Do Not Call" case, the telemarketers had sought to overturn a decision this year by the U.S. 10th Circuit Court of Appeals in Denver to uphold the "Do Not Call" registry, which has put more than 60 million phone numbers off limits to telemarketers.
The appeals court rejected industry arguments that such regulation violated free-speech protections because there's a distinction between charitable or political calls and commercial solicitations.
Today, the Supreme Court let stand the appeals court decision without comment.
The Federal Trade Commission has been allowed to collect phone numbers for the "Do Not Call" registry as numerous legal challenges were settled. Telemarketers face fines of up to $11,000 for each call that violates the regulation.
In recognition of the law's popularity, the Direct Marketing Association, the nation's largest group representing telemarketers and other related firms, advised its members this year to refrain from contacting those who registered their phone numbers regardless of the legal outcome.
"The DMA's members had decided earlier this year not to pursue further litigation against the National Do Not Call Registry," said association President John A. Greco, Jr. in a statement. "Our members include the vast majority of the teleservices industry, and they remain committed to respecting the wishes of those who have placed their household telephone numbers on the do-not-call list. Today's decision changes nothing."
In another business case, the high court rejected an appeal by Visa and MasterCard, which have been found in violation of anti-competitive rules for prohibiting its member banks from also offering American Express and Discover cards.
The federal government, which filed an antitrust suit against the two credit card networks in 1998, claimed that both companies were trying to stifle competition and innovation by imposing illegal restrictions on banks that accepted their cards.
"The Supreme Court's decision means the end, once and for all, of Visa and MasterCard rules that have prevented banks from issuing cards on rival networks," said American Express Chairman Kenneth I. Chenault in a statement. "In effect, the court has decided that these rules are illegal and must be abolished. The appeals are over."
Times wire services contributed to this report.