Probable cause is a legal standard in U.S. criminal law that requires a reasonable basis to believe that a crime has been committed or that evidence of a crime is present in a specific place. It is necessary for law enforcement to make arrests, conduct searches, or obtain warrants. This standard is more than mere suspicion but less than the evidence needed for conviction, requiring facts and circumstances sufficient to lead a prudent person to believe that a suspect is involved in criminal activity
. Key points about probable cause include:
- It is rooted in the Fourth Amendment, which protects against unreasonable searches and seizures and mandates probable cause for warrants
- Probable cause can justify arrests and searches, including some warrantless searches under exigent circumstances
- It is a stronger standard than reasonable suspicion, which allows brief stops and questioning but not arrests or searches
- Probable cause is based on concrete facts and trustworthy information, not just hunches or vague suspicions
- Examples include police seeing illegal drugs in plain view or hearing a gunshot and seeing someone flee with a weapon, which can justify immediate action
In summary, probable cause is the reasonable belief, supported by facts and evidence, that justifies law enforcement actions like arrest and search, balancing individual rights with public safety
