1911 Encyclopædia Britannica/Nolle Prosequi
NOLLE PROSEQUI (sometimes shortened into nol. pros.), a technical term of English law, the meaning of which varies as it is used with reference to civil or criminal cases. In civil cases it applied only to actions in the king’s bench division, and there signified a formal undertaking by the plaintiff that he intended to proceed no further with the action (se ulterius nolle prosequi). The more modern practice in such cases is to proceed by way of discontinuance. In proceedings either by indictment or by information, a nolle prosequi or stay of proceedings may be entered by the attorney-general. The nolle prosequi is a matter purely for his discretion, and will not be granted unless very good ground be shown for his interference. The object of it generally is to obtain a stay of proceedings against an accomplice in order to procure his evidence. This object is, however, more usually effected by the prosecution offering no evidence and the judge directing an acquittal.
In the United States the term bears the same meaning as in England, with one exception. The attorney-general has not the same discretion with which English law invests him. Although in some states the prosecuting officer may enter a nolle prosequi at his discretion, in others the leave of the court must be obtained.