Lower Merion Criminal Lawyer, Pennsylvania

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.

A deliberate act that causes harm to another, for which the victim may sue the wrongdoer for damages. Acts of domestic violence, such as assault and battery, are intentional torts (as well as crimes).

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.

An agreement to do something or to allow something to happen, made with complete knowledge of all relevant facts, such as the risks involved or any available alternatives. For example, a patient may give informed consent to medical treatment only after the healthcare professional has disclosed all possible risks involved in accepting or rejecting the treatment. A healthcare provider or facility may be held responsible for an injury caused by an undisclosed risk. In another context, a person accused of committing a crime cannot give up his constitutional rights--for example, to remain silent or to talk with an attorney--unless and until he has been informed of those rights, usually via the well-known Miranda warnings.

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).

An affirmative defense to a crime. Self-defense is the use of reasonable force to protect oneself from an aggressor. Self-defense shields a person from criminal liability for the harm inflicted on the aggressor. For example, a robbery victim who takes the robber's weapon and uses it against the robber during a struggle won't be liable for assault and battery since he can show that his action was reasonably necessary to protect himself from imminent harm.

A mental defect or disease that makes it impossible for a person to understand the wrongfulness of his acts or, even if he understands them, to ditinguish right from wrong. Defendants who are criminally insane cannot be convicted of a crime, since criminal conduct involves the conscious intent to do wrong -- a choice that the criminally insane cannot meaningfully make. See also irresistible impulse; McNaghten Rule.