At the beginning of the movie when the "Scorpio Killer" shoots his first victim, he leaves a note for the city to pay a ransom. Scorpio leaves the note stuck on an antenna by running an arm of the antenna through the note. While in the Mayor's office they have the note on an overhead projector so that everyone (including the audience) can read the note. At that time you can clearly see that there is no hole punched through the paper. Even if the hole were folded back to it's original form, there should still be a scar of some kind visible.