People in New Jersey are protected from unreasonable searches of the their person and property. What is reasonable depends on the circumstances though. As many people may have found, one of the reasons police can search people and vehicles is if they have probable cause to believe that people may have committed a crime.
Prior to the legalization of marijuana in the state, police were able to conduct searches of vehicles and people if they smelled marijuana. As possession of marijuana was a crime, if police smelled it when they stopped a vehicle, they could then legally search the vehicle for evidence of the crime. While they were searching the vehicle, if they found evidence of other crimes, people could be charged for those as well.
Smell of marijuana not enough to justify search
The legalization of marijuana changes these rules. Police can no longer search a vehicle after a stop simply because they smell marijuana, whether burned or raw. Police can still expand the stop to determine if the driver is under the influence of marijuana, but if the driver is clearly not under the influence the police cannot conduct a further search and must let the driver leave.
This is true for stops of individuals as well. Police can no longer stop and search people in public simply because they smell marijuana on people. There must be other evidence of a crime for police to justify stopping and searching individuals.
Police have been able to use the smell of marijuana to justify stops and searches of people and vehicles in New Jersey for a long time. Many times the searches led to more serious criminal charges though based on what police found. Now that police cannot use the smell of marijuana alone to justify searches, people now have an extra protection against unreasonable searches. It also may provide them additional defenses in the event that they are charged for a crime based on an illegal search.