These are trained professionals in maintaining law and order and know how to use weapons. They also have the license to stop crime within their area of jurisdiction.
In order to become a cop, there are many requirements including a clean criminal record, passing of written exams and being physically able enough.
They have to work within the limits of their police department and cannot be involved in work outside their limits. Police officers are present all over the world.
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Sheriffs are elected officials in most states of the US. They were first around in the 1600s. They are trained in law enforcement and are also involved in the affairs of the state or the county in which they perform their duties.
Generally the Sheriff does not indulge in direct police work and leaves it to the local police department but can do so whenever he or she deems it to be fit.
The Sheriff has a wide range of area under him or her and can also work as a coroner’s office in case of need. Often Sheriffs have had some prior law enforcement experiences as well.
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