Massachusetts (i/ˌmæsəˈtʃuːsɨts/), officially the Commonwealth of Massachusetts, is a U.S. state in the New England region of the northeastern United States of America. It is bordered by Rhode Island and Connecticut to the south, New York to the west, and Vermont and New Hampshire to the north; at its east lies the Atlantic Ocean. Massachusetts is the 7th least extensive, but the 14th most populous and the 3rd most densely populated of the 50 United States. The state features two separate metropolitan areas – the eastern Boston metropolitan area and the western Springfield metropolitan area. Approximately two thirds of the state's population lives in Greater Boston, most of which is either urban or suburban. Western Massachusetts features one urban area – the Knowledge Corridor along the Connecticut River – and a mix of college towns and rural areas. Massachusetts is the most populous of the six New England states and has the US's sixth highest GDP per capita.
A police officer (also known as a policeman or policewoman, and constable in some forces, particularly in the United Kingdom and other Commonwealth nations) is a warranted employee of a police force. In the United States, "officer" is the formal name of the lowest police rank; in many other countries "officer" is a generic term not specifying a particular rank, and the lowest rank is often "constable". Police officers are generally charged with the apprehension of criminals and the prevention and detection of crime, and the maintenance of public order. Police officers may be sworn to an oath, and have the power to arrest people and detain them for a limited time, along with other duties and powers.
Some police officers may also be trained in special duties, such as counter-terrorism, surveillance, child protection, VIP protection, and investigation techniques into major crime, including fraud, rape, murder and drug trafficking.
Responsibilities of a police officer are varied, and may differ greatly from within one political context to another. Typical duties relate to keeping the peace, law enforcement, protection of people and property, and the investigation of crimes. Officers are expected to respond to a variety of situations that may arise while they are on duty. Rules and guidelines dictate how an officer should behave within the community, and in many contexts restrictions are placed on what the uniformed officer wears. In some countries, rules and procedures dictate that a police officer is obliged to intervene in a criminal incident, even if they are off-duty. Police officers in nearly all countries retain their lawful powers, while off duty.