The Las Vegas cases, involving William Molina and Marques Butler, both 17 years old at the time, have attracted the attention of several national groups, some of whom have been asked by the court to weigh in on the constitutionality of Nevada's "presumptive certification" law.

"It's a great opportunity for us to comment on a crucial issue of criminal justice," said Lee Rowland, an attorney with the ACLU.

The law says juveniles age 14 or older suspected of using or threatening to use a deadly weapon in a crime are presumed to be eligible for prosecution as adults.

Molina is charged with crimes involving the armed robbery of a Las Vegas taco shop in 2006. He has said he was not involved in the crime.

Butler is charged with several crimes arising from the armed robbery of two men in a Las Vegas park in 2006.

Both were sent to adult court for prosecution.

Both are represented by Las Vegas attorney Kristina Wildeveld, who has raised constitutional issues in the cases.

A date for arguments in the two cases, which have been combined, has not yet been set by the Supreme Court.

By pleading not guilty to the charges, Williams automatically was transferred to adult court, the brief said.

To stay out of adult court, the law allows a juvenile to present evidence that emotional, behavioral or substance abuse problems contributed to the commission of the crimes.

But to use the process successfully, juveniles essentially have to plead guilty to the crimes for which they are charged by undergoing psychological evaluations and other types of testing, the brief said.

And once the determination has been made on whether to prosecute in juvenile or adult court, any of the information presented seeking to keep a case in juvenile court can be used against the youth in further court proceedings, a violation of due process rights, the brief said.

"Highly prejudicial facts presented to maintain juvenile court jurisdiction may be used against the child at any stage in the criminal process," the brief said.

Lourdes Rosado, an attorney with the Juvenile Law Center, said Nevada's law creates a non-choice for juveniles.

The juvenile either admits to a crime in an effort to stay in juvenile court, requiring an unconstitutional act of self-incrimination, or is sent to adult court for prosecution, she said.

"We don't want kids to be put in that position," Rosado said. "The consequences are huge for juveniles."

Molina faces up to 36 years in prison if convicted as an adult. He faces a minimal sentence in juvenile court.

Rosado said other states use an evaluation process to determine whether a youth should be tried in juvenile or adult court, but the information gathered to make such a determination is limited to that use only and cannot be used later for prosecution.

The Clark County district attorney's office, in a response brief filed in Molina's case, argued that the law does not violate a juvenile's constitutional rights.

All that must be shown to keep a case in juvenile court is that substance abuse or one of the other identified factors contributed to a juvenile's delinquent acts, the response said.

Rosado praised the Supreme Court for seeking participation from the Juvenile Law Center and the other organizations.

"The court wants to get all the best information, the best arguments, in front of it," she said.