Anonymous tipsters have more credibility under

a closely divided Supreme Court decision Tuesday that upheld the tip-incited search of a California man's truck. In a case that atypically split the justices, the court's 5-4 majority concluded California Highway Patrol officers acted reasonably when they stopped and searched the truck after hearing about a reckless driver. During the August 2008 search in Mendocino County, the officers found 30 pounds of marijuana.

"We have firmly rejected the argument that reasonable cause for an investigative stop can only be based on the officer's personal observation, rather than on information supplied by another person," Justice Clarence Thomas wrote for the majority in Navarette vs. California.

Liberal Justice Stephen G. Breyer joined Thomas and three other court conservatives in the decision.

Conservative Justice Antonin Scalia, often allied with Thomas, joined three liberal dissenters.

"Drunken driving is a serious matter, but so is the loss of our freedom to come and go as we please without police interference," Scalia wrote. "To prevent and detect murder we do not allow searches without probable cause or targeted . . . stops without reasonable suspicion. We should not do so for drunken driving either."

Justices appeared highly skeptical of laws that try to police false statements during political campaigns, raising doubts about the viability of such laws in more than 15 states.

Justices expressed those concerns often Tuesday during arguments in Susan B. Anthony List v. Driehaus, challenging an Ohio law that bars people from recklessly making false statements about candidates seeking elective office.

The case has attracted wide attention, with both liberal and conservative groups saying the law tramples on a time-honored, if dubious, tradition of political mudslinging.

The case began during the 2010 election when a national antiabortion group, the Susan B. Anthony List, planned to put up billboards accusing then-Rep. Steve Driehaus of supporting taxpayer-funded abortion because he voted for President Obama's health-care law. Driehaus, a Democrat who opposes abortion, claimed the group's billboard ads distorted the truth and therefore violated the false-speech law.

The court is not expected to rule directly on the constitutional issue because the current question before the justices is only a preliminary one: Can you challenge the law right away, or do you have to wait until the state finds you guilty of lying?

Justice Anthony M. Kennedy said there's "a serious First Amendment concern with a state law that requires you to come before a commission to justify what you are going to say."

- Inquirer Wire Services