Differentiate between 'reasonable suspicion' and 'probable cause' and explain how each standard applies to law enforcement actions under the Fourth Amendment.

'Reasonable suspicion' and 'probable cause' are distinct legal standards under the Fourth Amendment, which protects against unreasonable searches and seizures. 'Reasonable suspicion' is a lower standard than probable cause. It requires that a law enforcement officer have specific and articulable facts, taken together with rational inferences from those facts, that would lead a reasonable person to believe that criminal activity is afoot. This is a less demanding standard than probable cause and requires a showing considerably less than preponderance of the evidence. Reasonable suspicion allows for a brief investigatory stop or detention, often referred to as a 'Terry stop', and a limited pat-down for weapons if the officer reasonably believes the person is armed and dangerous. 'Probable cause' is a higher standard, requiring that the officer have a reasonable belief, based on trustworthy facts and circumstances, that a crime has been committed or is being committed and that the person or place to be searched is connected to the crime. It requires more than a mere suspicion; there must be sufficient evidence to lead a reasonable person to believe that a crime is likely occurring or has occurred. Probable cause is required for more intrusive law enforcement actions, such as arrests, searches of homes or vehicles, and the issuance of warrants. For example, an officer might have reasonable suspicion to stop someone walking late at night in a high-crime area who is acting nervously and glancing around. This reasonable suspicion allows the officer to briefly detain the person to ask questions and potentially conduct a pat-down for weapons. However, to arrest that person or search their backpack, the officer would need probable cause – for instance, seeing the person discard a bag containing drugs or receiving information from a reliable informant that the person is dealing drugs. The Fourth Amendment dictates that more intrusive actions require a higher level of justification, hence the difference between 'reasonable suspicion' and 'probable cause'.