This guide exists as both an introduction to resources commonly used in Maryland legislative history research, and a how-to guide for getting your answers efficiently. Where appropriate, I have provided the location of the resources being discussed, or, where online, a URL. Please report any broken links to me at firstname.lastname@example.org, and they will be remedied with a quickness.
Legislative history is a specialized sort of research designed to trace the development of a particular statute or larger statutory scheme through a legislative body. For Maryland law, this often involves tracking amendments; following the trail through prior codifications of the Maryland Annotated Code; and reviewing the session laws to obtain bill numbers, and the House and/or Senate Journals to uncover changes made during the process of enactment. Recent enactments may have recorded proceedings available as well. For in-depth research, bill files contain documentary submissions received during deliberations on the bill.
Statutes are, for lack of a better term, a framework--a loose structure designed to account for certain classes of human behavior. Our elected representatives enact them in order to achieve some desired result--e.g., the curtailment of the drug trade; increase in tax revenue; protection of the Chesapeake Bay. That said, human behavior is defined by its resistance to prediction, which is problematic for drafters of legislation. If the statute is written in explicit terms throughout, the drafters may wind up with a law too narrow for its intended goal, exempting certain behavior the drafters had intended to cover. On the other hand, if the law is written in vague terms, it may prove overbroad, and thereby subject to attack as unconstitutional.
What legislative drafters attempt to do is achieve a sort of middle ground, viz., a statute circumscribed enough to avoid collateral attack, while at the same time broad enough to allow courts to adapt it to unforeseen circumstances. This rationale--or occasionally simple bad drafting--may result in ambiguous language. So, when faced with an ambiguous statute, courts attempt to determine the "legislative intent" of the drafters, and this is where the legislative history comes in. By tracing the development of a statute back to its original introduction as a bill--or perhaps beyond--we get a better sense of what the General Assembly hoped to accomplish, guiding us in applying the law to particular cases.