商场和私人party还是不一样的。对商场来说，关键是证据，

......
“Though these laws vary, store owners and their employees generally are allowed to detain an individual when they have probable cause to suspect shoplifting. However, any such detention of a suspected shoplifter must be reasonable in length and manner. Detentions without probable cause, for an unreasonable amount of time, or in an unreasonable manner may leave the store open to liability for false imprisonment and possibly other claims. ”
criminal.findlaw.com/criminal-charges/shoplifting.html

有证据，商家就不会输，否则，商家就吃不了，兜着走。