3rd Amendment
This Amendment forbids the quartering of soldiers in private homes in times of peace. It also prohibits the practice in time of war except "in a manner to be prescribed by law." There are always guarantees added to prevent what had been British practice in the colonial days. The Amendment actually has had almost no importance since its adoption. It has never been a subject of a Supreme Court case.
4th Amendment
This Amendment also grew out of colonial practice. It was really designed to prevent the use of writs of assistance - blanket search warrants with which British customs officials had invaded private homes in order to search for smuggled goods. Unlike the 3rd Amendment, this one has proved a highly important guarantee. There is a general rule laid down by this guarantee also: Police Officers have no general right to search for evidence or to seize either evidence or persons.
Probable Cause
Police can arrest a person in a public place without a warrant provided they have probable cause to believe that person is about to commit or has commited a crime. Officers don't need a warrant in many situations. They do not need one when evidence is "in plain view."
An arrest is the seizure of a person. When officers make a lawful arrest of a person, they do not need a warrant to search the area within which he might gain possession of a weapon or destructable evidence. Most arrests do end up taking place without a warrant. Polive can arrest a person in a public place without one, provided they have probable cause.
Probable Cause
Police can arrest a person in a public place without a warrant provided they have probable cause to believe that person is about to commit or has commited a crime. Officers don't need a warrant in many situations. They do not need one when evidence is "in plain view."
An arrest is the seizure of a person. When officers make a lawful arrest of a person, they do not need a warrant to search the area within which he might gain possession of a weapon or destructable evidence. Most arrests do end up taking place without a warrant. Polive can arrest a person in a public place without one, provided they have probable cause.