The U.S. Supreme Court derailed a key part of Arizona's campaign finance system on Tuesday by at least temporarily blocking extra money for publicly funded candidates outspent by privately financed rivals or targeted by independent groups' spending.

The court said in a brief order that it will prevent the state from using its system of so-called matching funds at least until the justices decide whether to hear the full appeal of opponents of the key provision of the state's campaign funding system.

Distribution of matching funds was to start June 22, but it could be the fall before the court decides even whether to accept the case. Arizona's primary election is Aug. 24.

Publicly funded candidates get matching funds when they're outspent by privately funded rivals or targeted by independent groups' spending.

Critics contend matching funds chill free-speech rights of privately financed candidates and their contributors by inhibiting fundraising and spending. State officials defend matching funds, saying they help combat contributions-for-favors corruption and encourage more people to run for office. Also, blocking matching funds would be disruptive to candidates already committed to running with public funding, officials argued.

State regulators and the New Mexico Environmental Law Center are asking the justices to order a District Court judge in Lovington to reverse an earlier decision that halted the effort by New Energy Economy to control greenhouse gas emissions.

Judge William Shoobridge granted a preliminary injunction in April that prohibited the state Environmental Improvement Board from continuing proceedings on New Energy Economy's petition.

Petition supporters argue that if allowed to stand, the judge's ruling would cripple state agencies' ability to carry out appointed responsibilities. They say the high court must hear the case because it raises questions about separation of powers and judicial interference in an administrative process.

New Mexico's largest utility, four state lawmakers and other industry groups sued in January to stop the Environmental Improvement Board from considering the petition. New Energy Economy and regulators countered with a motion to dismiss the lawsuit, a move that Shoobridge rejected.

Public Service Company of New Mexico, one of the plaintiffs, has argued that a state cap on greenhouse gas emissions would be costly for businesses and utility customers and that the emissions debate should be settled by the federal government.

The British branches of Vodafone, Telefonica O2, T-Mobile and Orange had argued against the EU's imposing maximum price limits for "roaming" charges or extra fees for making or receiving calls outside the user's home nation.

The European Court of Justice dismissed their arguments, saying the EU's executive commission did not abuse its powers when it fixed limits for roaming fees across the 27-nation bloc in 2009.

Europeans have long complained about high roaming fees they were being charged.

"That high level of retail charges had been regarded as a persistent problem by public authorities and consumer protection associations," the court said in a statement.

It said the average level of roaming charges in the European Union was euro1.15 ($1.37) per minute, more than five times the actual cost that telecommunications companies paid to transfer the calls to each other.

The court also backed the maximum price set by EU regulators, saying they had carefully examined the economic impact.

Judge Victoria Chaney met with lawyers in closed session regarding new claims of witness tampering, then took the bench to abruptly announce there had been threats to her and to witnesses in radio addresses in Nicaragua.

She said she was notifying the judicial protective unit.

"This appears to be flagrant witness tampering," she said. "I have even more grave concerns about witness safety than I did before."

Chaney didn't reveal the source of the threats, and transcripts of the broadcasts haven't been released. She did say the tampering didn't appear to involve plaintiff's attorney Steve Condie.

Los Angeles is home to hundreds of medical marijuana dispensaries, but concern over their proliferation has provoked a backlash. Police are cracking down on most of them starting Monday.

A new city ordinance limits the number and locations of medical marijuana dispensaries allowed to operate in Los Angeles. Those that registered with the city before a 2007 moratorium may be able to remain in business. But they can't be near schools, libraries, parks and other sensitive areas. Police officers will begin closing down 400 unregistered dispensaries now operating illegally.

"The sky isn't going to fall down," says Asha Greenberg, assistant city attorney. "LAPD isn't going to go around kicking down doors, etc. Initially we're going to be doing information gathering."

Greenberg says L.A.'s new ordinance makes it a misdemeanor to run a dispensary without city approval.

"Anyone who is operating a medical marijuana establishment, who is violating the city's ordinance is subject to arrest," Greenberg says.

Dispensary owners and patients have filed more than 20 lawsuits against the city, arguing that the ordinance is unconstitutional because it prohibits access to their medicine. So far, their attempts at temporary restraining orders have been turned down in court.

The Supreme Court won't hear arguments that Hillary Rodham Clinton is ineligible to be secretary of state.

The high court on Monday refused to hear an appeal by Judicial Watch, a conservative watchdog group.

The Constitution says no member of Congress can be appointed to a government post if that job's pay was increased during the lawmaker's current term. Clinton was serving as New York senator when the secretary of state's salary was raised to its current level of $191,300.

Congress lowered the salary so that Clinton could take the position.

Judicial Watch says the congressional fix doesn't change the fact that Clinton's appointment was illegal.