Flat Rock Juvenile Law Lawyer, Illinois, page 5

A rule of evidence that disallows the use of illegally obtained evidence in criminal trials. For example, the exclusionary rule would prevent a prosecutor from introducing at trial evidence seized during an illegal search.

An exception to the general rule that a police officer needs an arrest warrant before he can enter a home to make an arrest. If a felony has just occurred and an officer has chased a suspect to a private house, the officer can forcefully enter the house in order to prevent the suspect from escaping or hiding or destroying evidence.

The killing of one human being by the act or omission of another. The term applies to all such killings, whether criminal or not. Homicide is considered noncriminal in a number of situations, including deaths as the result of war and putting someone to death by the valid sentence of a court. Killing may also be legally justified or excused, as it is in cases of self-defense or when someone is killed by another person who is attempting to prevent a violent felony. Criminal homicide occurs when a person purposely, knowingly, recklessly or negligently causes the death of another. Murder and manslaughter are both examples of criminal homicide.

Latin for 'You have the body.' A prisoner files a petition for writ of habeas corpus in order to challenge the authority of the prison or jail warden to continue to hold him. If the judge orders a hearing after reading the writ, the prisoner gets to argue that his confinement is illegal. These writs are frequently filed by convicted prisoners who challenge their conviction on the grounds that the trial attorney failed to prepare the defense and was incompetent. Prisoners sentenced to death also file habeas petitions challenging the constitutionality of the state death penalty law. Habeas writs are different from and do not replace appeals, which are arguments for reversal of a conviction based on claims that the judge conducted the trial improperly. Often, convicted prisoners file both.

A jury unable to come to a final decision, resulting in a mistrial. Judges do their best to avoid hung juries, typically sending juries back into deliberations with an assurance (sometimes known as a 'dynamite charge') that they will be able to reach a decision if they try harder. If a mistrial is declared, the case is tried again unless the parties settle the case (in a civil case) or the prosecution dismisses the charges or offers a plea bargain (in a criminal case).

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.

Listening to conversations or observing conduct which is meant to be private, typically by using devices that amplify sound or light, such as stethoscopes or binoculars. The term comes from the common law offense of listening to private conversations by crouching under the windows or eaves of a house. Nowadays, eavesdropping includes using electronic equipment to intercept telephone or other wire communications, or radio equipment to intercept broadcast communications. Generally, the term 'eavesdropping' is used when the activity is not legally authorized by a search warrant or court order; and the term 'surveillance' is used when the activity is permitted by law. Compare electronic surveillance.

A formal investigation -- governed by court rules -- that is conducted before trial. Discovery allows one party to question other parties, and sometimes witnesses. It also allows one party to force the others to produce requested documents or other physical evidence. The most common types of discovery are interrogatories, consisting of written questions the other party must answer under penalty of perjury, and depositions, which involve an in-person session at which one party to a lawsuit has the opportunity to ask oral questions of the other party or her witnesses under oath while a written transcript is made by a court reporter. Other types of pretrial discovery consist of written requests to produce documents and requests for admissions, by which one party asks the other to admit or deny key facts in the case. One major purpose of discovery is to assess the strength or weakness of an opponent's case, with the idea of opening settlement talks. Another is to gather information to use at trial. Discovery is also present in criminal cases, in which by law the prosecutor must turn over to the defense any witness statements and any evidence that might tend to exonerate the defendant. Depending on the rules of the court, the defendant may also be obliged to share evidence with the prosecutor.