Do police have to follow any particular rules in arresting me and searching for opioid drugs?

Yes, any time the police make an arrest, it has to be based on probable cause. What that means is, would a reasonable officer, in that particular situation, under those circumstances believe that a crime had been committed? Once there’s been a lawful arrest, in other words, one based on probable cause, the police are then allowed under the fourth amendment to conduct a search incident to arrest. Once they’ve lawfully arrested you, they can then search you and your property. If they have not lawfully arrested you, in other words, the arrest was not based on probable cause, in other words, a reasonable officer in that situation would not have made an arrest, then the search following that arrest, incident to that arrest, is unlawful, and a judge could throw out the evidence, which means that the case could ultimately be dismissed.