TRENTON - A Texas man arrested with 21 guns in his car while passing through New Jersey four years ago will remain in prison after an appeals court on Monday upheld his conviction in a case that could wind up in front of the state Supreme Court.

Dustin Reininger is serving a five-year sentence with a three-year minimum before he is eligible for parole.

A jury convicted him in absentia in 2010 on several weapons counts including illegal possession of shotguns, rifles, hollow-point bullets, and a high-capacity magazine after police found him sleeping in his car behind a bank in Readington early March 20, 2009.

Reininger, who was listed as living in Rockport, Texas, initially denied having guns in the car, but after they noticed two firearms cases on the backseat, police searched the vehicle and found 14 rifles, four shotguns, and three handguns, along with the bullets and magazine. Reininger told police he was moving to Texas from Maine and transporting the weapons, which his attorney says he legally owned.

Attorney Evan Nappen said Monday that the warrantless search of his client's vehicle was troubling, and said he likely would appeal Monday's ruling to the state Supreme Court on that and other grounds. The three-judge panel also denied Reininger's claim that New Jersey's gun laws violate the Second Amendment.

According to Monday's ruling, police are allowed to conduct a warrantless search under a "plain view" exception if potentially suspicious evidence is within their view and they were unaware of its existence beforehand. Monday's decision diverged from the trial court's conclusion that safety concerns were enough for the officer to search Reininger's vehicle, but still allowed the search.

The "plain view discovery of firearm cases on the backseat, and defendant's subsequent admission that he was transporting long arms to Texas," gave the officer probable cause to believe Reininger possessed firearms illegally, the judges wrote.

"All the officers saw were cases," Nappen said. "The court is essentially saying the plain view of a gun case is a basis for a warrantless search. That means every law-abiding gun owner in New Jersey is subject to warrantless search if they transport their firearms in a gun case.

"My recommendation to all gun owners is to transport all firearms in guitar cases," he added.

The appeals court rejected Reininger's argument that the indictment should have been dismissed because prosecutors didn't tell grand jurors about a federal exemption for interstate transport of firearms. But the judges noted that federal law requires guns not stored in a trunk - which Reininger's SUV didn't have - to be stored "in a locked container other than the glove compartment or console" so they are not directly accessible by someone in the car.

State law is similar, requiring that guns be "carried unloaded and contained in a closed and fastened case, gunbox, securely tied package, or locked in the trunk," according to the court ruling.