High Court Asked to Reject Measure M : Taxation: Foes say the transportation initiative unconstitutionally imposes a levy. Backers are not worried about the challenge.

Opponents of Orange County’s recently approved transportation sales tax filed a California Supreme Court challenge to the measure Thursday, firing the first shot in a new battle over the County Transportation Commission’s right to collect and spend a tax that voters solidly approved.

“We warned them that we were going to do this,” said Bill Ward, a leader of Drivers for Highway Safety, which opposed Measure M in the November election. “We told them they should look at the constitutionality of the tax, but they went ahead anyway.”

Measure M, which adds a half-cent to the county sales tax, is expected to raise $3 billion for transportation improvements. Supporters herald it as the key to unlocking the county’s snarled traffic, while opponents say it unfairly raises taxes and will pave the way for more development.

Supervisor Thomas F. Riley, who led his colleagues in supporting Measure M, said he was not concerned about the possibility of a legal challenge.

“I’ve relied on our legal experts for years, and I have no reason to doubt them on this,” he said.

Although the legal motion filed Thursday raises several objections to Measure M, at the heart of the issue is whether the measure, which passed, 54.8% to 45.2%, should have required two-thirds approval and not a simple majority. In their motion, plaintiffs argue that Proposition 13, the landmark 1978 tax initiative, requires two-thirds approval of a tax increase such as Measure M.

Members of the County Transportation Commission, however, contend that Measure M required only a simple majority.

New questions have arisen regarding the legal status of special sales taxes. A similar case involving a San Diego sales tax for law enforcement, for instance, is now before the Supreme Court; Measure M foes hope that the justices will hear the cases together.

It is extremely rare for the Supreme Court to accept a case that has not been heard by a lower court. But Santa Ana attorney Mark S. Rosen, representing foes of Measure M, said he hopes that the similarities between the San Diego case and Orange County’s will lead the court to accept the motion from Measure M opponents.

Underlying the disagreement over Measure M is a long series of cases regarding Proposition 13 and its application to local governments and so-called “special districts.”

In 1982, the Supreme Court upheld the right of the Los Angeles County Transportation Commission to impose a half-cent tax after winning a majority of county votes. In that case, the Supreme Court ruled that organizations that cannot levy property taxes--including transportation commissions--are not bound by Proposition 13’s requirement that special taxes be approved by two-thirds of the electorate.

Based on that ruling, the Los Angeles panel was allowed to collect and spend its sales taxes for transportation improvements.

But in 1986, California voters approved Proposition 62, which broadened Proposition 13’s reach, extending the two-thirds requirement to any agency created to perform a governmental function.

After passage of that tax initiative--which has also been contested with mixed results in lower courts--San Diego’s case has emerged as an important test of the ability of local governments to raise taxes. In the San Diego case, a special commission sought approval of a half-cent sales tax for law enforcement. The tax passed, but just barely.

A Superior Court judge then ruled the tax invalid, saying it needed a two-thirds majority, but he was overruled last fall by an appellate court. The Supreme Court has agreed to decide the matter, with its ruling closely watched by county governments across the state.

Despite the complex and ambiguous court precedents, Orange County officials remain confident that they will prevail.

“If the Orange County sales tax measure isn’t bulletproof, then no measure in California is bulletproof,” said Stanley Oftelie, executive director of the Orange County Transportation Commission. “We’ve modeled our measure exactly on the previous court rulings and the experiences of other counties.”