The Fourth Amendment requires a search to be based on probable cause. That is, government investigators must have a rational belief that a crime has been committed and that evidence or fruits of the crime can be found. The question courts will ask when a citizen claims to have been unconstitutionally searched is whether that person had a reasonable expectation of privacy in the place, papers, or information that government agents have examined or taken.

In a society that both deplores crime and values liberty, there will always be a tension between law enforcement interests and the privacy of individuals. The modern age has increased the ability of criminals to hide crime and its proceeds, and law enforcement sometimes struggles to keep up. This sometimes inspires investigative methods that trample on the privacy expectations and Fourth Amendment rights of innocent citizens. The U.S. Supreme Court has not been a powerful guardian of the Fourth Amendment in recent years, further eroding some Fourth Amendment protections.

In addition, the growth of both the U.S. and state governments during the 20th century vastly increased the amount of information that governments collect. When information is collected for "administrative" purposes, like issuing licenses and benefits or collecting taxes, the government does not have to satisfy the Fourth Amendment. Unfortunately, sometimes this information is used by investigators, released or sold by government agencies, or just misused by rogue government employees. This invades citizens' expectations of privacy and violates their Fourth Amendment rights.

Links:

Rescuing Search and Seizure by Stephen Budiansky, The Atlantic Monthly (October 2000)

Comments? comments@privacilla.org (Subject: FourthAmendment)

[updated 10/30/00]