Most adult Americans have seen their fair share of crime-based television shows involving conduct within police precincts and out on the street as law enforcement officials go about their jobs. Such shows also frequently delve into the conduct of and interactions among defense attorneys, prosecutors and judges.

Story lines in such presentations often seek to emphasize criminal law processes, procedures and standards. As such, evidence often takes a central role. Was the gun recovered by cops obtained legally or will be it deemed inadmissible in court by a judge? Did police officers have a right to enter an apartment, or did they first require a warrant?

The term “probable cause” often makes an entry into criminal law plots and twists both in fictionalized dramas and every day in real life in towns and cities across the United States.

Probable cause is a bedrock principle of long standing in criminal jurisprudence, being specifically mentioned in the Fourth Amendment of the nation’s Constitution. Police officers and prosecutor must often establish probable cause prior to taking actions relating to enforcement and investigation.

What exactly is probable cause? In simple terms and in the context of police/citizen interactions, it means that an officer must have a reasonable belief that a crime was committed or that ongoing criminal activity is being carried out prior to taking any enforcement action. There are permutations on that theme in different situations, but they all centrally revolve around the notion that a police officer cannot proceed under guise of pretext or in an arbitrary fashion. Rather, some reasonable basis must exist to search or arrest a person, enter a dwelling and take other enforcement actions.

Probable cause can be a bit of a slippery slope, and it is critically important when any issue of evidence admissibility arises. Any person with questions or concerns regarding this important criminal law concept can get answers — and strong legal representation when required — from a proven criminal defense attorney.

Source: FindLaw, “Probable cause,” author uncited, accessed Oct. 24, 2014