What are the major exceptions to searching without a search warrant?

Question

What will be an ideal response?

Answer 1

There are cases where warrants are not necessary, although these are fairly narrowly defined by the courts. The first is the consent search. These types of searches are permissible without a warrant and without probable cause as long as consent has been voluntarily given by a person who has authority to give consent and the scope of the search doesn't exceed the consent given.
Vehicle searches are also exempt from the warrant requirement. The logic behind allowing warrantless searches of vehicles is that there is a reduced expectation of privacy. Vehicles also create an exigency in that they are inherently moveable.
Open-field searches are another type of search that can take place without a warrant. The Supreme Court has held that open fields outside the curtilage surrounding buildings or homes are not constitutionally protected and are therefore allowable without a search warrant. There is no reasonable expectation of privacy in an open field.
Another situation in which a search warrant is not required is an exigent situation known as the evanescent evidence exception. In this case, evidence is likely to disappear in the time it would take to get a warrant. Plain-view searches may also be conducted without a warrant.
Stop and frisk searches are another example of the warrantless search. These are conducted in the interest of officer safety and/or crime prevention.
Finally, searches incident to a lawful arrest are allowable without a search warrant. In these cases, officers are allowed to search the area under the immediate control of the suspect, which is essentially their armspan. In an automobile, this includes the entire passenger compartment of the vehicle, including the glove box if it is unlocked.