A body-cam video that shows a New Jersey state trooper conducting a roadside strip search has sparked controversy and raised questions about how far law enforcement officers are permitted to go during a traffic stop.

Trooper Joseph Drew had pulled a car over for tailgating and said he smelled marijuana. When a search of the car turned up nothing, he handcuffed the driver and told him to step out of the vehicle.

"You can tell me where it is right now or I can go in and get it," Drew says on the video.

The trooper is then seen pulling on blue latex gloves, reaching into the driver's underwear, and groping his genitals and buttocks while the two stand on Route 206 in Southampton, Burlington County.  All the while, trucks and cars pass by on the busy highway.

The driver, a 23-year-old Toms River, N.J., man, insisted several times he had no marijuana and said he doubted such a search was legal.

No drugs were found in the man's car or on his body, and in the end he was issued a ticket for tailgating. The driver has filed notice of intention to sue, alleging that he was sexually assaulted and that his civil rights were violated.

In the video, the driver can be heard protesting that he is being sexually assaulted as the trooper repeatedly touches his genitals during a four-minute search of the man's underwear.

Earlier, the trooper checked the man's pockets and socks and ordered him to turn over drugs, the footage shows. Then he told him, "If you think this is the worst I'm going to do, you have another thing coming, my friend."

Experts in policing were critical of the trooper's actions.

Maria Haberfeld, a professor of policing and police ethics at John Jay College of Criminal Justice and an author of several books on the subject, said the search was unwarranted.

"To reach into someone's underwear, it has to be for a really good reason, not for marijuana," she said. "In the times when marijuana has been legalized in state after state, this is some kind of erratic police behavior — and it's very much about discretion, so even if you can do things, should you be doing them?"

State Police Internal Affairs is investigating the incident, which occurred on March 8, 2017.  Drew and a backup trooper, Andrew Whitmore, are still on patrol pending the outcome of that inquiry. Neither could be reached for comment, and their union, the New Jersey State Police Fraternal Association, said it would have to check with its lawyer before releasing any statement on the matter.

The incident came to light last week, when the video was posted on the website of John Paff, who heads New Jersey Libertarians for Transparency, an open government group. Paff obtained the body-cam and dashcam videos of both troopers after filing open public records requests in January. He was checking the court docket, as he does routinely, and came across the driver's legal filing.

The video footage shocked him.  "It was extreme, in my view, because of the cavalier attitude, the way this cop acted," he said.  "This is outrageous."

Lt. Theodore Schafer, a state police spokesman, declined to comment on the search and declined to say whether troopers have the authority to conduct such searches under such circumstances.  He said he could not release the agency's policy on searches, saying it is not public record.

Arthur Lang, a Lakewood attorney who represents the driver, said in court documents that he has been unable to obtain a copy of the policy despite several requests made in the last three months. Last month, he filed a motion seeking a court order to compel the state police to provide it.

Efforts to reach the driver were unsuccessful. The Inquirer and Daily News are withholding the man's name because the newspapers do not identify victims of alleged sexual assault without their permission.

Schafer said troopers must follow the rules outlined in a policy issued by the state attorney general, but he said the state police also have detailed requirements of their own on how and when to conduct searches.

The Attorney General's Office has a six-page strip search and body cavity search policy that is 23 years old and contains a very general list of "requirements and procedures" for law enforcement officers to follow. A spokesman for the office, Peter Aseltine, declined to elaborate or respond to general questions about such searches.

"I am not authorized to interpret the requirements and procedures, and we do not have any further comment," Aseltine wrote in an e-mail.  He also declined to comment on the search conducted by the trooper.

The attorney general's policy says anyone who is detained or arrested, but not placed in jail, may not be strip or body cavity searched without a search warrant or consent and authorization by a superior.  However, in emergencies, such searches may be performed if  law enforcement officers have "probable cause to believe that the person is concealing a weapon, contraband or evidence of crime."

The policy also says strip searches must be "conducted by person of same sex …  in private … under sanitary conditions and … in a professional and dignified manner."

Body cavity searches should not be performed unless someone is jailed, the policy says in bold letters. Such a search is defined as a "visual inspection or manual search of a person's anal cavity, vaginal cavity."  In this case, the driver contends that he was subjected to a strip search and visual body cavity search.

Amol Sinha, executive director of the American Civil Liberties Union of New Jersey, said troopers must have probable cause for such a search and said "it's debatable whether the smell of marijuana is sufficient."  He said he was appalled that the search was conducted "on a roadside in a humiliating and undignified way" and that the justification for that was the odor of marijuana.

In Sinha's view, the case illustrates the need to legalize marijuana.  "These are exactly the kinds of harms that can occur when the state is dead set on enforcing unjust marijuana laws," he said.  Such laws ruin people's lives, he said, because they end up with a criminal record for possessing a substance deemed by health experts to be less harmful than alcohol or tobacco.

Lang, the driver's lawyer, said in court filings that the state police and prosecutors failed to provide his client with the videos until 10 months after the incident occurred, despite frequent requests.

In order to sue the state police, the driver must first file a tort claim asking the court to waive the government's immunity against lawsuits. The 90-day deadline for filing that claim has expired, but Lang said the court should allow the claim to go forward because the state police have not given him the information he needs to proceed.

The tort claim seeks permission to sue Drew and Whitmore, a desk sergeant who may have approved the search when Drew radioed him from the road, and state police.

In court filings, the Attorney General's Office argues the claim should be dismissed because it was filed late.  "Ignorance of the law is not an excuse," it said.

Regardless of whether a lawsuit goes forward, Sinha, of the ACLU, said the state police and the Attorney General's Office must address the public's concerns about the videos.  He also said Drew should not remain on patrol while the matter is being investigated.

"Trust in  law enforcement suffers when incidents like this happen and we see no accountability," he said. "We need assurances it won't happen again, and that the state police amends its policies, training, and procedures … so the public can trust that the police are looking out for the people they serve."