Without context there is no way to provide a meaningful answer. There are occasions when they certainly do, and occasions when they certainly do not need a warrant.
For instance, if they are investigating one thing and drugs are obviously sticking out of the bag, then it is in plain sight. That is enough for an arrest, and they can then search as subsequent to an arrest. But even then, they might want to detain the bag's owner at the scene and wait on a warrant.
Another situation where no warrant is needed is when dealing with minors and the parents and/or school grant's permission. The school owns the school building and the lockers and thus can grant permission to search.
not if you let him search it
Tough question: On the one hand, the police need a warrant or Probable Cause to assume a crime is being committed to perform a de facto search of your bag. On the other hand, the police are allowed to make sure there is no weapon in the purse that could endanger them. Of course, this raises the question of, why did they detain you, too. So you're in a very tricky legal area. It is very much a matter of local legislation.
It depends on who they are, who you are, if they have a warrant or reason to search, and what you are trying to do.
Yes you need
The idea behind a 'search warrant' is that you have a reasonable expectation of privacy, and the warrant gives the police a legal right to invade that privacy. So if they want to search you, your property, or your vehicle, they need that warrant. However, the outside of your vehicle does not have that expectation of privacy. An officer does not need a warrant to inspect your car's outside more closely, whether it is to check the condition of the tyres, the presence of paint scrapings, or perhaps to narrow down the location of a suspicious odour. On a side note, in some places an officer can 'search' inside a vehicle without a warrant, ie, if he saw a bag of cannabis on a car seat, through the window, he could use that as probable cause to get a formal search warrant to retrieve it. Things left out in the open like this inside a vehicle have a lowered expectation of privacy.
If the cop has a warrant or if he thinks you stole something or if the cop thinks you have a weapon in a place you are not suppose to have the weapon.
There has to be another reason you were arrested other than "asking the police why they were searching your property" why were they there?
Hey. You need to give the country and/or state. (In many parts of the world where the police previously did not have this power, it has been given to them in the last 8-9 years under anti-terrorism laws).
A school administrator cannot search your car, or your bag, unless he has your permission (Although not letting him is basically admitting guilt). Off the school premises, if he searches your car, he is basically breaking and entering your vehicle. He would need to call the police for a warrant.
After being pulled over for driving with a suspended license, a search by police of Santana's Bentley found a bag of marijuana, 29 bullets and $20,500 in cash inside a plastic bag.
This just means they have a warrant to search what you have and to take anything they find incriminating as evidence. The warrant will likely have a scope, saying they can only look in certain places or only for certain types of evidence. So if they have a warrant to look for just a gun possibly used in a murder, they cannot seize a joint or a bag of dope.
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