Unless done so at the direction of the state (i.e. an officer is telling the person to do it), this is not true. While there may be a state or two that holds private citizens to this standard, that is not the case in most states.
LP does not need a search warrant to search a person or their property, and if they detain people they are not acting as agents of the state - they hold their own liability as specified in the statutes if they use excessive force to affect the detention or arrest, or make an unlawful detention or arrest.
There might be consequences for an unlawful detention or arrest if you nab someone to search their bag or person without cause, but you are not an agent of the state nor are you able to even seek a search warrant.
Laws vary by state in this area. To make a blanket statement that LP or other retail folks are "agents of the state" when they affect a detention or an arrest is simply NOT TRUE. Nor must they seek a search warrant to conduct a search since they are legally unable to do so.
Here is a good discussion of how these laws apply in my state of CA:
http://le.alcoda.org/publications/fi...CESEARCHES.pdf
The above link states that, even if a mall security guard conducts an unlawful search, the fruits of that unlawful search are admissible because that guard is not an agent of the police. Fine.
But, if the guard is not an agent of the police, and he is conducting an unlawful search, I have the right to physically resist that search. And, knowing that the fruits of the illegal search will be admissible in court, I just might have an incentive to resist to the extent that I seriously injure that guard.
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I'm not sure that signs would make a search legal. If I post a sign saying that anyone who comes into my store will be punched, that doesn't mean that I can legally punch a person.
That depends on the circumstances and the state. If you are detained/arrested pursuant to state law for a crime committed in the presence of the person doing the detention, they may very well have the right to conduct a search of your person and possessions if for no other reason than their safety!
Some states may have a law that specifically precludes a private person search, but, there is no specific statute that makes it a crime for a private person to snoop inside of another's personal property and there are laws that prevent you from battering others - especially if you have been detained or arrested under the law. Not to mention the fact that using force in the commission of a theft is something we call "robbery" (as mentioned by WhosThatGuy above) which is a violent and serious felony.
A security guard can snoop into my bag only if the bag is just sitting there, out of my hands. But what if I am holding the bag and I am using force to prevent the guard from snooping into the bag?
And how would a guard just snoop into my pockets? I can use force to stop him from doing that.
If you use force, you could be charged with battery. If you use force to conceal stolen goods, it's robbery.
And if you did, you could also be charged with crimes under applicable state including - as I mentioned - battery and/or robbery, depending on the facts.And how would a guard just snoop into my pockets? I can use force to stop him from doing that.
Most (perhaps ALL) states permit the reasonable use of force to safely detain people. Part of this detention can include - at a minimum - a search for weapons. If you resist, they may be permitted to use reasonable force to overcome that resistance.
Again, it all depends on applicable state law and there are 50 of them plus the District of Columbia, so your mileage may vary as to the specifics. But, you have no sacred right to be secure in your pockets and pocketbook when it comes to a search or an arrest even by a private individual. The concept of reasonableness generally applies.