Justice League of America, Vol. 1

Dr. Destiny creates a duplicate League and has them overcome their real counterparts one by one. The fake League then commit crimes, tricking the world into believing that the real heroes have become villains. They are banished from Earth. On a spaceship taking them away from the planet, the League reveal their identities to each other and return to Earth in their civilian guises where they battle the fake Leaguers. Capturing them, they take them to the same judge who banished them who now clears them of all blame. At the end of the story, Superman thinks it is best if both the world at large as well as each other forgets their identities and plans to use Amnesium to wipe every one's memories.