The difference between "reasonable suspicion" and "probable cause" is that:

1) Police may only 'stop and frisk' someone if they have probable cause to do so.
2) Probable cause requires a higher level of proof on the part of the police.
3) The police need to obtain neither when they are working in high-crime areas.
4) Reasonable suspicion is all that is needed to arrest someone.

The main difference between 4) 'reasonable suspicion' and 'probable cause' involves the level of proof required; 'reasonable suspicion' is a lower threshold allowing for stop and frisks, while 'probable cause' is needed for arrests and search warrants.

Explanation:

The difference between "reasonable suspicion" and "probable cause" is crucial in understanding law enforcement powers and citizens' rights. Reasonable suspicion is a lower standard than probable cause and allows police to stop and frisk individuals if they suspect a crime is being committed, has been committed, or will soon be committed.

This is established in the landmark case Terry v. Ohio (1968). However, probable cause requires a higher level of proof and is necessary for obtaining search warrants and making arrests without a warrant for felonies.

It is the belief based on factual evidence that a crime has been committed or that evidence of a crime can be found in the place to be searched.