Understanding the structure of our government is a key to being able to find the law. The United States Constitution sets out how the three branches of government are organized and work together at the federal level. The Massachusetts Constitution delineates the workings of three branches at the state level.
At the Federal level, the U.S. Congress (the legislative branch) passes Public Laws in numerical order in two year sessions. These session laws are then organized by subject and codified into the U.S. Code, available from www.thomas.gov. The many agencies of the executive branch promulgate regulations that are published in the Code of Federal Regulations. The United States district courts (the judicial branch) are the trial courts of the federal court system. The 94 U.S. judicial districts are organized into 12 regional circuits, each of which has a United States Court of Appeals. Massachusetts is in the First Circuit. The U.S.Supreme Court is the highest tribunal for all cases and controversies arising under the Constitution or the laws of the United States, and as such is the final arbiter of the law.
On the state level, Massachusetts legislative branch’s session laws are known as the Acts and Resolves. Our current codification is called the Massachusetts General Laws. Both are available at the General Court’s (a.k.a. Legislature’s) website. As with the federal material, the Commonwealth’s executive branch agencies promulgate regulations collectively known as the Code of Massachusetts Regulations. The Massachusetts Court System consists of seven Trial Courts and two appellate courts (the Massachusetts Appeals Court and the Supreme Judicial Court). Appellate court decisions are considered precedential and they are published and available on the web.
At the local level, municipal bylaws and ordinances have the force of law, with their authority derived from the statutes (Mass. General Laws). They are indexed by city and town when available at http://www.lawlib.state.ma.us/source/mass/bylaws.html.
Knowing whether the law that you are looking for comes from the legislative, executive or judicial branch is a great help in being able to find it.