Saint Ignatius Juvenile Law Lawyer, Montana

A lawyer who is elected to represent a state government in criminal cases in a designated county or judicial district. A D.A.'s duties typically include reviewing police arrest reports, deciding whether to bring criminal charges against arrested people and prosecuting criminal cases in court. The D.A. may also supervise other attorneys, called Deputy District Attorneys or Assistant District Attorneys. In some states a District Attorney may be called a Prosecuting Attorney, County Attorney or State's Attorney. In the federal system, the equivalent to the D.A. is a United States Attorney. The country has many U.S. Attorneys, each appointed by the President, who supervise regional offices staffed with prosecutors called Assistant United States Attorneys.

Latin for a 'guilty act.' The actus reus is the act which, in combination with a certain mental state, such as intent or recklessness, constitutes a crime. For example, the crime of theft requires physically taking something (the actus reus) coupled with the intent to permanently deprive the owner of the object (the mental state, or mens rea).

Punishment in a criminal case. A sentence can range from a fine and community service to life imprisonment or death. For most crimes, the sentence is chosen by the trial judge; the jury chooses the sentence only in a capital case, when it must choose between life in prison without parole and death.

A legal doctrine that prevents legislators from being sued for actions performed and decisions made in the course of serving in government. This doctrine does not protect legislators from criminal prosecution, nor does it relieve them from responsibility for actions outside the scope of their office, such as the nefarious activities of former Senator Bob Packwood.

The crime of breaking into and entering a building with the intention to commit a felony. The breaking and entering need not be by force, and the felony need not be theft. For instance, someone would be guilty of burglary if he entered a house through an unlocked door in order to commit a murder.

A court official usually classified as a peace officer (sometimes as a deputy sheriff, or marshal) and usually wearing a uniform. A bailiff's main job is to maintain order in the courtroom. In addition, bailiffs often help court proceedings go smoothly by shepherding witnesses in and out of the courtroom and handing evidence to witnesses as they testify. In criminal cases, the bailiff may have temporary charge of any defendant who is in custody during court proceedings.

The mental component of criminal liability. To be guilty of most crimes, a defendant must have committed the criminal act (the actus reus) in a certain mental state (the mens rea). The mens rea of robbery, for example, is the intent to permanently deprive the owner of his property.

A peace officer for a particular geographic area -- most often a rural county -- who commonly has the power to serve legal papers, arrest lawbreakers and keep the peace. Depending on the state, a constable may be similar to a marshal or sheriff.