Dorchester is a dissolved municipality and current neighborhood of Boston, Massachusetts, United States. It is named after the town of Dorchester in the English county of Dorset, from which Puritans emigrated and is today endearingly nicknamed "Dot" by its residents. Dorchester, including a large portion of today's Boston, was separately incorporated in 1630. It was still a primarily rural town and had a population of 12,000 when annexed to Boston in 1870. Railroad and streetcar lines brought rapid growth, increasing the population to 150,000 by 1920. It is now a large working class community with many African Americans, European Americans (and is still a center of Irish American immigration), Caribbean Americans, Latinos, and East and Southeast Asian Americans. Recently, there has been an influx of young professionals, gays and lesbians, and working artists to the neighborhood, adding to its diversity.

May 30, 1630, Captain Squib of the ship Mary and John entered Boston Harbor and on June 17, 1630 landed a boat with eight men on the Dorchester shore, at what was then a narrow peninsula known as Mattapan or Mattaponnock, and today is known as Columbia Point (more popularly since 1984 as Harbor Point). Those aboard the ship who founded the town included William Phelps, Roger Ludlowe, John Mason, Samuel Maverick, Nicholas Upsall, Henry Wolcott and other men who would become prominent in the founding of a new nation. The original settlement founded in 1630 was at what is now the intersection of Columbia Road and Massachusetts Avenue. (Even though Dorchester was annexed over 100 years ago into the city of Boston, this founding is still celebrated every year on Dorchester Day, which includes festivities and a parade down Dorchester Avenue).

Boston (pronounced /ˈbɒstən/ or locally /ˈbɔstən/ ( listen)) is the capital of and largest city in Massachusetts, and is one of the oldest cities in the United States. The largest city in New England, Boston is regarded as the unofficial "Capital of New England" for its economic and cultural impact on the entire New England region. The city proper, covering only 48.43 square miles, had a population of 617,594 according to the 2010 U.S. Census. Boston is also the anchor of a substantially larger metropolitan area called Greater Boston, home to 4.5 million people and the tenth-largest metropolitan area in the country. Greater Boston as a commuting region is home to 7.6 million people, making it the fifth-largest Combined Statistical Area in the United States.

In 1630, Puritan colonists from England founded the city on the Shawmut Peninsula. During the late 18th century, Boston was the location of several major events during the American Revolution, including the Boston Massacre and the Boston Tea Party. Several early battles of the American Revolution, such as the Battle of Bunker Hill and the Siege of Boston, occurred within the city and surrounding areas. Through land reclamation and municipal annexation, Boston has expanded beyond the peninsula. After American independence was attained Boston became a major shipping port and manufacturing center, and its rich history now helps attract many tourists, with Faneuil Hall alone attracting over 20 million every year. The city was the site of several firsts, including America's first public school, Boston Latin School (1635), and the first subway system in the United States (1897).

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.