In determining that prohibition did not lie to challenge the appointment of a special district attorney to investigate election law issues, the Second Department explained:
” [A]n article 78 proceeding in the nature of prohibition will not lie to correct procedural or substantive errors of law'” (Matter of Soares v Herrick, 20 NY3d 139, 145, quoting Matter of Schumer v Holtzman, 60 NY2d 46, 51). Rather, “the extraordinary remedy of prohibition may be obtained only when a clear legal right of a petitioner is threatened by a body or officer acting in a judicial or quasi-judicial capacity without jurisdiction in a matter over which it has no power over the subject matter or where it exceeds its authorized powers in a proceeding of which it has jurisdiction” … . Even where prohibition is an available remedy, it ” is not mandatory, but may issue in the sound discretion of the court'” … . ” In exercising this discretion, various factors are to be considered, such as the gravity of the harm caused by the excess of power, the availability or unavailability of an adequate remedy on appeal or at law or in equity and the remedial effectiveness of prohibition if such an adequate remedy does not exist'” … .
Prohibition is an available remedy to void the improper appointment of a Special District Attorney pursuant to County Law § 701 when the Special District Attorney is performing the quasi-judicial act of representing the State in its efforts to bring individuals accused of crimes to justice … . However, it is not an available remedy when the Special District Attorney is performing the purely investigative function of investigating “suspicious circumstances” with a view toward determining whether a crime has been committed, since, in such circumstances, his or her acts are to be regarded as executive in nature … . Here, the WFP failed to establish that Special District Attorney Adler was performing a quasi-judicial act. Accordingly, prohibition does not lie. Matter of Working Families Party v Fisher, 2013 NY slip Op 05578, 2nd Dept 8-7-13