Early on, Oakland Circuit Judge David Breck dismissed the charges, ruling that an undercover operation entrapped Johnson. Prosecutors disagreed and appealed the decision.
Supreme Court arguments are the culmination of the process, and could change the guidelines for how entrapment is decided in Michigan in the future.
Michigan courts currently use an "objective test," which tries to prevent police from creating a crime where none would have occurred, to decide whether someone was entrapped.
But the state Supreme Court asked both sides if Michigan should use the "subjective test" -- used by federal courts and most other states -- to decide if police have crossed the line. The federal standard focuses on what the accused was thinking -- in short, whether police lured a noncriminal into committing a crime.
Both the defendant and the prosecutor in Johnson's case favor sticking with the present rule. So does Michigan Attorney General Jennifer Granholm, in a friend of the court brief.