NAPLES, Fla. - Alex Crain, the 14-year-old boy arrested in the shooting deaths of his parents, has been charged as an adult with two counts of manslaughter with a firearm.

Each count, a first-degree felony, carries a maximum 30-year prison sentence.

Crain is accused of shooting parents Thomas and Kelly Crain in the family’s Golden Gate Estates home on Dec. 9. He was originally arrested on a pair of second-degree murder charges.

Crain is at the Naples Jail Center, where he is being held in medical housing as “a precaution,” Collier County Sheriff’s Office spokeswoman Michelle Batten said. He would be moved to a juvenile wing of the jail when medically cleared, Batten said.

“He’s separated from other adults,” she said.

Crain will appear on Thursday before a Collier Circuit judge, who will determine whether to set a bond for the teenager.

Tuesday’s formal filing by Assistant State Attorney Richard Montecalvo follows a lengthy review of the case by the State Attorney’s Office. Crain’s family and attorneys sought to have him charged as a juvenile, a path that would result in milder penalties than an adult filing.

A psychiatric evaluation of Crain was conducted on behalf of the state, and Crain’s attorneys had two more performed, the results of which they shared with prosecutors.

“(The decision) was based on all of the facts and evidence we are able to review at this time,” State Attorney’s Office spokeswoman Samantha Syoen said.

Crain’s grandmother, Nancy Ward, declined comment on Tuesday.

Reached by phone, Crain attorney Mark Rankin said he and co-counsel Brian Bieber anticipated the filing, following a conversation with prosecutors.

Although the adult filing goes against the family’s wishes, Rankin said they were heartened murder charges were not filed.

“It’s culpable negligence instead of intent to kill,” he said of the distinction. “And I think the state looked at our doctors’ reports and their own doctor’s report and evaluated the unique circumstances—that he’s such a young kid, that it’s his parents.”

Second-degree murder carries a maximum life sentence in prison.

Little evidence has been released publicly in the case. Deputies found the bodies of Thomas, 40, and Kelly, 39, in the master bedroom of their home at 4240 47th Ave. NE, following an emergency call from the home at 8:30 a.m.

Crain was the only other person inside the home.

Evidence of what happened before the shooting, and Crain’s mindset, have yet to be made public.

Such factors are central to a prosecutor’s determination of how to file against a juvenile, said Abe Laeser, a Dade County attorney who spent 36 years as a prosecutor in the 11th Circuit State Attorney’s Office in South Florida.

Not all crimes are created equal, and neither are all juveniles, Laeser said. The psychiatric evaluations in Crain’s case likely plumbed the teenager’s maturity, as well as his mental state.

“Ultimately I’m going to try to get as much information as I can about the sophistication of the child,” he said. “Age of course is an issue, their mental history, if known, their school history.”

More evidence will come out of the case once the state begins sharing its evidence with Crain’s defense attorney.

The case is one of several high-profile homicides involving juveniles in recent months.

Last August, 13-year-old Jonathan Rowles was arrested after Collier detectives say he shot and killed his mother in their East Naples home. Prosecutors charged Rowles with a manslaughter as a juvenile.

In January, deputies arrested Jorge Saavedra, 14 at the time, on a manslaughter charge after they say he stabbed fellow Palmetto Ridge High student Dylan Nuno, 16, during a fight outside a Golden Gate Estates bus stop. Prosecutors charged Saavedra last week with armed manslaughter, as a juvenile.

Crain, like Saavedra, was a freshman at Palmetto Ridge High School.

Past homicide cases involving juveniles tried as adults have received heavy attention in the media. Among the most notorious are the Lords of Chaos and Cash Feenz, both Lee County cases involving older juveniles.

In the Lords of Chaos case, a gang of teens that included 17-year-old Pete Magnotti murdered high school Mark Schwebes. Magnotti is now serving a 32-year prison sentence.

The Cash Feenz killings saw three juveniles charged and sentenced as adults in the murders of teenagers Alexis and Jeffrey Sosa. Ashley Toye and Roderick Washington, both 17 at the time, were sentenced to life. Iriana Santos, 16 at the time, pleaded and received 25 years.

In Collier, teenagers Mazer Jean and Jermaine Jones received life sentences after murdering a guard at an Ochopee juvenile detention camp in 1998. Jean was 17 at the time; Jones was 16.

Other juvenile homicide cases are less aggravated, involving vehicle crashes or accidents.

In a recent Collier case, Riccardo Rivas, 18, pleaded no contest on Tuesday to a vehicular homicide charge from a 2009 crash. Rivas, who was 16 at the time of the accident, was sentenced as a youthful offender to one year in prison and four on probation.

Crain’s attorneys may seek the same designation. A youthful offender distinction during sentencing caps a defendant’s maximum incarceration at six years, to be served in a separate facility from adult prisoners.

“That’s at least within the realm of possibilities,” Rankin said of the designation.

Laeser, the former prosecutor, said the program has a downside. A youthful offender who violates probation may face the full guideline sentence, he said.