DANVERS — When Danvers police Chief Neil Ouellette spotted a pair of young men leaning into a truck in a Route 1 parking lot one night last March, he suspected something was up.

But that hunch wasn't enough to justify detaining the two men and three others seated inside a nearby SUV, searching both vehicles, and arresting all of them on drug charges after one admitted to having a pound of marijuana in his truck, a judge has ruled.

Salem District Court Judge Robert Cornetta granted a motion by the men's lawyers to suppress the evidence, which also includes $4,600 in cash, several dozen oxycodone pills, a hammer and a notebook police believe contained records of drug transactions. His ruling was announced yesterday during a status hearing in the case.

He also granted motions by lawyers for three of the men, Harrison Lounsbury, 22, of Hamilton, Andrew Murley, 21, of Beverly and Jason Mostacci, 25, of Danvers, to dismiss the drug distribution and conspiracy charges pending against them.

Ryan Caverly, 30, and Joseph Olson, 23, both of Peabody, are still scheduled to go to trial next month in the case — but without any evidence left to present, a conviction is unlikely.

Steve O'Connell, a spokesman for the Essex County District Attorney's Office, said the decision is being reviewed and could be appealed by his office.

Ouellette was patrolling in the area on the evening of March 25, looking for possible suspects in a string of car breaks in which thieves were targeting GPS devices.

As he passed the Planet Fitness gym, he spotted the two men — later identified as Caverly and Olson — leaning into a white pickup truck.

The chief pulled into the lot and noticed a Lincoln Navigator SUV with tinted windows parked next to the truck. Because the Navigator had tinted windows, he didn't see the three other men inside.

The chief then called for backup. He got out and showed his badge to the men, who were carrying gym bags and said they were on their way into the gym. The chief ordered them to stop and asked for identification. Olson handed the chief his license and registration, but Caverly soon left and walked into the gym.

Both men's gym bags were empty.

Ouellette questioned Olson, telling him that a drug-sniffing dog was on the way to search the truck if Olson did not tell the truth.

Police testified that they found currency, a package of marijuana and the hammer in the truck.

As Olson was arrested, Ouellette sent other officers into the gym to arrest Caverly.

According to a police report, Caverly was dressed in street clothes as he stood near a weight machine.

Meanwhile, officers who arrived at the scene said they noticed "furtive movements" inside the Navigator through a partly opened window. The three men inside, Lounsbury, Murley and Mostacci, were ordered out and searched. Nothing was found on Murley. Mostacci was carrying $1,900 in cash and a notebook with names, monetary amounts and another $300 in cash inside. Lounsbury was later discovered to have oxycodone pills hidden in a cast on his arm.

Cornetta said there was no probable cause to support the search and arrests of Lounsbury, Murley and Mostacci. He also ordered police to return $1,900 to Mostacci.

As for Olson and Caverly, Cornetta ruled that police had no reason to detain either man and search the truck.

"There was no evidence found at the scene at that point of any break in or other crime afoot," the judge wrote. "There were no smashed windows observed, no pried open doors or trunks and no glass pieces on the pavement. The chief knew of no one in the Lincoln Navigator. At that point there was no further reason for the police to detain either Olson or Caverly."

The judge also noted that prosecutors had not presented evidence of the drugs and money during the hearing.

O'Connell, the district attorney's spokesman, said contraband and physical evidence is rarely introduced at such evidentiary hearings prior to trial. "It is standard practice in this commonwealth to rely upon the testimony of police officers with regard to the evidence that was seized." It is a practice supported by case law and is also intended to prevent any of the evidence from being compromised prior to trial.

Oullette, reached for comment on the ruling, said he would not do anything different.

"If I'm driving through a parking lot and I think a crime is going on, I'd still try to find out what was going on," the chief said.

"We make decisions in a split second all the time," Ouellette said. "The court has days and weeks and months to evaluate those decisions."