The tough new guidelines of the federal courts intended to make sentences more uniform were struck down by the 9th U.S. Circuit Court of Appeals as an unconstitutional violation of the separation of powers between the judicial and executive branches of government.

The decision Tuesday will govern in nine Western states under the 9th Circuit's jurisdiction until a ruling, possibly next year, by the U.S. Supreme Court.The appeals court said federal judges should not have been allowed to serve on the seven-member commission that created the guidelines.

Requiring judges to sit as presidential appointees on the commission violated the constitutional separation of powers, the court held in a 2-1 decision.

Numerous cases challenging the guidelines arose around the nation, but Tuesday's ruling was the first by an appeals court.

The guidelines, which went into effect last Nov. 1, were most criticized by civil libertarians and criminal defense lawyers, who said they took discretion away from individual judges and often resulted in sentences that were unconscionably long.

Writing for the majority, Judge Alex Kozinski, a conservative Reagan appointee, said, "We can prevent undue entanglement by the judiciary in the operation of the political branches only by adopting a clear-cut, prophylactic rule: Congress may not, under our system of separated powers, require judges to serve on bodies that make political decisions."

Kozinski was joined by Judge Melvin Brunetti, also a Reagan appointee.

Judge Charles Wiggins, a former U.S. senator and also a Reagan appointee, dissented. He said the Sentencing Reform Act "does not offend the Constitution. No branch of government has been negatively affected by the allocation of power made by it."

Lower courts have been sharply split by the issue. In Los Angeles 23 district judges divided 13-10 to hold against the guidelines.

In separate cases three federal judges ruled in San Diego. Two struck down the rules and one upheld them.

The sentencing guidelines resulted from a decadelong effort by Congress to minimize wide disparities in sentences given defendants with similar records convicted of the same crimes.

Under the guidelines, judges were required to impose relatively uniform sentences based on several given factors. The judges could deviate from the guidelines only by making specific findings of mitigating or aggravating factors.

Tuesday's 9th Circuit decision will put us "back at square one," said Nanci Clarence, a federal public defender in San Francisco.

She said the decision will create immediate and complex problems in criminal cases in which defendants have plea-bargained and cooperated with the government and are awaiting sentencing.