“Trucking”, a 1970′s song by the Grateful Dead, contains the cryptic line “if you've got a warrant, I guess you're gonna come in”. While under most circumstances, the band was right, the majority of searches are conducted by police officers without a court authorized warrant. In speaking with clients in my practice, I have come to realize that most people have little understanding as to when a warantless search is justified and unfortunately when they unknowingly surrender their constitutional protections against illegal searches of their persons, possessions and homes.

The 4th Amendment to the U.S. Constitution protect citizens against “unreasonable” searches and seizures. While the courts have consistently held that warrantless searches are presumed to be unreasonable, exceptions to this rule have been carved out over time, based upon a balancing of individual rights versus the general public's need for crime detection and public safety.

The most common exception to the warrant requirement occurs following arrest. Police may search an individual and the area within his immediate control at the time of arrest. When the person has been arrested while driving an automobile, this “area of control” has come to include the entire interior of the vehicle and the trunk.

Even without an arrest, police may search the interior of an automobile if they have probable cause to believe that the vehicle contains contraband or evidence of a crime which they have reasonable suspicion to believe has occurred. This is often the case when police conduct a traffic stop and detect the odor of marijuana emanating from the interior of the vehicle. The logic behind this exception is that automobiles are by nature, moveable, and while people still have an expectation of privacy inside their cars, a temporary detention and search based on probable cause is more efficient than having to expend the time to obtain a search warrant.

As an aside however, during my 15 years as a prosecutor, I drafted numerous search warrants for vehicles believed to contain large quantities of drugs, weapons or other contraband. A search warrant in those cases eliminated the need to have to later justify the warrantless search to the judge at a motion to suppress.

Where police are confronted with circumstances which suggest an immediate threat to public safety, no search warrant is required. This is commonly referred to as the “public safety” exception, most readily exemplified in circumstances where a firearm is believed to be hidden either on a person or in a place which threatens the safety of others.

Police are trained to request consent to search a person's vehicle, home and physical person where they have a suspicion, but no articulable probable cause to believe that a crime has been committed or contraband present. So long as there is no evidence of overreaching or coercion, consent searches are valid. Unfortunately, many people, when confronted by a police officer at their door or roadside following a routine traffic stop, believe they must comply with the officer's request to search. Remember, consent means just that – it is a right which only you can surrender.

If the police impound an automobile or other conveyance, they have the right to conduct what is often referred to as an “inventory” search. Technically, this intrusion is justified to protect the police from subsequent claims that they lost or destroyed property located inside the vehicle. As such, it is really not a “search” at all, but rather an effort to reduce police liability. Regardless, any evidence or contraband located during an inventory is admissible at all subsequent court proceedings.

The protection against unreasonable searches and seizures was included in the Constitution as a response to the British soldiers habit of breaking down the doors of the Colonials to search for evidence of crimes. Fortunately, that right continues to this day, except for the defined exceptions discussed herein which have been the subject of much litigation and court rulings for over 200 years. As times and technology change, there will undoubtedly be additional challenges to this essential constitutional protection. As a result, a working knowledge of the rights afforded by the 4th Amendment remains as essential today as it did in post-colonial times.