Washington ? The Supreme Court agreed Monday to try to settle whether long-established rules for sentencing criminals in federal court were constitutional, a question the justices raised with a ruling in June that placed thousands of criminal cases in limbo.

The justices threw federal courthouses into disarray by overturning a state sentencing system that is similar to the one used by federal judges. In the case from Washington state, the high court said the rules gave judges too much sway in determining the length of prison terms.

In a rare summer announcement, the justices said they would hear two cases about the sentencing dilemma on their first day back to work in October.

In the six weeks since the high court ruling, some federal judges have concluded that it rendered the federal sentencing system unconstitutional. Other judges have continued using the old sentencing system. In one Utah courthouse, four different federal judges have taken four different views about whether the system could stand.

“Right now it’s just a mess. People don’t know what to do,” said Roscoe Howard, former U.S. attorney for the District of Columbia and now a Washington lawyer.

With federal judges handing out about 1,200 criminal sentences a week, the number of cases that may be affected by the uncertainty is staggering, the Bush administration’s top Supreme Court lawyer argued in court filings.

“The number of federal cases affected by the questions presented in these cases will increase dailya until this court resolves those questions,” acting Solicitor General Paul Clement argued in asking the high court to move quickly.

The administration defends the federal system, set up by Congress in 1987 as a way to make sentencing more uniform and fair. Judges are given a range of possible sentences for each crime.

Although judges frequently complain that the guideline system leaves them too little flexibility, the rules also rely on judges to make many factual decisions that can affect a sentence, such as the amount of drugs involved in a crime, or whether a gun was used.

The Supreme Court’s 5-4 ruling in Blakely v. Washington held that juries must decide any matter that can lengthen a sentence beyond the maximum set out in state sentencing guidelines unless the defendant admits to it.

To do otherwise violates a defendant’s Sixth Amendment right to a jury trial, the court majority said.

The high court long ago ruled the federal guideline system constitutional but has since begun a re-examination of the role of judges and juries in determining facts.