Ross (defendant) was arrested pursuant to an informant’s tip that he was selling illegal drugs kept in the trunk of his car. District of Columbia police officers stopped Ross’ car and conducted a search. During the search, the officers found a bullet on the driver’s seat. The officers then searched the glove compartment and discovered a gun. Ross was placed under arrest. After arresting Ross, the officers took his keys and opened the trunk of his car. In the trunk, they found a brown paper bag. The officers opened the paper bag and discovered clear plastic bags containing what appeared to be drugs. The car was transported to the police station, where another search of the trunk uncovered a zippered leather pouch. A search of the pouch revealed that it contained a large sum of cash. Ross moved to suppress the introduction at trial of the contents of the paper bag and zippered pouch. The trial court denied Ross’ motion and he was convicted at trial. A panel of the court of appeals concluded that Ross had a greater expectation of privacy with respect to the contents of the zippered pouch than with respect to the contents of the paper bag. The panel upheld the judgment of conviction based on the admissibility of the paper bag evidence. The court of appeals en banc reversed the panel decision and vacated the judgment of conviction. The United States (plaintiff) petitioned the United States Supreme Court for review.