Martin went into a convenience store bathroom and refused to come out (he was apparently in there for long enough to alarm the employees, who knocked on the door and tried to get him to leave). Eventually, a store clerk called the police and asked them to remove Martin from the premises entirely.
The cops knocked on the door and identified themselves, ordering Martin out. He eventually responded that he was using the bathroom and would be out shortly. When he did come out, he was reluctant to comply with the officers' instructions and told them he would do whatever he wanted because he was on private property. He was agitated and nervous.
The cops ordered him to face the wall and put his hands behind his back so they could pat him down for weapons. During the pat down that followed, Martin struggled. He and one of the officers were injured, and he was arrested. He was charged with trespass, resisting arrest, and attempting to disarm a peace officer (the trespassing charge was eventually dismissed by the prosecution).
Martin moved to suppress the evidence (his actions) as the fruits of an illegal detention and search. The court denied his motion, and he was convicted. He appealed.
In affirming the denial of Martin's motion, the Colorado Court of Appeals reviewed the difference between conssensual contacts, investigative stops, and arrests and the different levels of proof required for each one. The Court held that at the time of the encounter, police had reason to contact Martin both to check his welfare and based on reasonable suspicion that he was trespassing.
Regarding the search, the court decided not to decide whether or not the search was justified. Instead, the court held that even if the search hadn't been justified, any evidence that followed it was admissible because Martin committed a new crime during the search by resisting arrest and attacking the officers. Even if the entirety of the police conduct up to that point had violated the Fourth Amendment, evidence of Martin attacking the officers and resisting would be admissible.
The denial of Martin's motion to suppress was affirmed, but this case was remanded to the trial court for other reasons (basically, there was some confusion about whether or not Martin should have been allowed to testify after the defense rested its case. The Court of Appeals sent the case back to the trial court to decide whether or not it made the right decision after defining the test that it should use for that purpose. If the trial court sticks to its guns, Martin's conviction stands. If not, he gets a new trial).