Excessive force isn’t just hitting someone. He put her in handcuffs.
That's not true at all. Read what quotes I posted on the law. Excessive force is going beyond what is necessary to make an arrest.
Why does a mall security guard have handcuffs?
Mall cops shouldn’t be “arresting” anyone.
Well they have the authority to make a citizen's arrest if they see a crime occur, just as you and I do.
If I were a mall security guard I certainly wouldn't risk live or limb to arrest someone who shoplifts. I'd just get their license plate or picture. If they were on foot you may have to follow them or something, could arrest them I guess, but I wouldn't. Only time I might arrest someone as a security guard is if someone were an active threat like committing violence and they needed to be cuffed.