Color of is a legal term meaning "pretense or appearance of" some right; in other words, 'color of', as in 'color of law', means the thing colors (or adjusts) the law; however the adjustment made may either be lawful or it may merely appear to be lawful.
Color of law refers to an appearance of legal power to act but which may actually operate in violation of law. For example, though a police officer acts with the color of law authority to arrest someone, if such an arrest is made without probable cause the arrest may actually be in violation of law. In other words, just because something is done with the 'color of law', that does not mean that the action was actually lawful.
The Supreme Court has interpreted the United States Constitution to construct laws regulating the actions of the law enforcement community. Under 'color of law', it is a crime for one or more persons using power given to him or her by a governmental agency (local, state or federal), to willfully deprive or conspire to deprive another person of any right protected by the Constitution or laws of the United States. Enforcement of 'color of law' does not require that any racial, religious, or other discriminatory motive existed. Criminal acts under color of law include acts within and beyond the bounds or limits of lawful authority. Off-duty conduct may also be covered if official status is asserted in some manner.
Color of law may include public officials and non-governmental employees who are not law enforcement officers such as judges, prosecutors, and private security guards. Furthermore, in many states it is unlawful to falsely impersonate a police officer, a federal officer or employee, or any other public official or to use equipment used by law enforcement officers, such as flashing lights or a fake police badge. "Possession of a firearm also can enhance the penalty for false impersonation of a police officer."
Color of office refers to an act usually committed by a public official under the appearance of authority, but which exceeds such authority. An act committed under color of office is sometimes required to prove malfeasance in office.
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