Though I generally CC, I will defend you're right to OC just as I always wear a helmet on my motorcycle, I will defend your legal right (in IN) not to wear one.
I am nearly always supportive of LEO but this guy behaved like a douche.
He never provided proof of being a LEO - badge or ID.
Make an appointment to talk to the Chief in person. When you leave the call back number, let the operator know that someone is impersonating a police office in Noblesville - detaining citizens. You've got a picture. You "wanted to let them know first so they can address it before you contact the television stations."
I would strongly urge you to assume the position that this was someone impersonating an officer until proven different.
Wait for the... "No. No... he's one of ours" from the Chief.
EDIT TO ADD: While the fake-cop is in the mood for a lecture, you might want to suggest he select the DIET Coke from the soda bar when he waddles up there.
Sounds like it was just a case of a cop power tripping and trying to impress those in the restaurant with his authority but he didn't expect a guy to actually stand up for himself.