Police officers were executing a search warrant at a home suspected of containing evidence of illegal gambling. No one was at home when the police arrived. After searching the first floor, the officers went upstairs. A friend of the owner then entered the house carrying a briefcase. He set the briefcase on the floor, opened it, and then heard the officers. He became frightened, left the briefcase sitting in the middle of the floor, and hid in a closet. The police officers returned to the first floor and immediately spotted the briefcase, which they knew was not there earlier. Because the briefcase was open, the officers saw its contents—betting slips—and seized them. Because they knew that someone had entered the house since they arrived, they re-searched the first floor. They found the friend and informed him that he was under arrest, clapped handcuffs on him, and read him his Miranda warnings. One of the officers patted the friend down to check for weapons. The officer noticed a bulge in the friend's pocket. Although the officer knew that the bulge was unlikely to be a weapon, he reached into the pocket anyway, and discovered a package that appeared to be (and later proved to be) heroin. The friend was charged with possession of narcotics. At a suppression hearing, will the court agree with the public defender's contention that the friend's arrest was unlawful?

A Yes, because the police officer who searched the friend knew that he did not have a weapon in his pocket.

B Yes, because the friend's mere presence in the house did not give the police probable cause to believe he had committed a crime, and they had no basis for searching him at all, because he did not act toward them in a threatening manner.

C No, because the contents of the briefcase gave the police probable cause to arrest the man.

D No, because the police had a right to search the friend for gambling slips, and the discovery of the heroin was merely incidental to a lawful search.