Proceeding pursuant to CPLR article 78 in the nature of prohibition and mandamus, inter alia, to compel the respondent John M. Galasso, a Justice of the Supreme Court, Nassau County, to vacate certain orders issued pursuant to CPL 330.20 and to prohibit the respondents from seeking any additional orders pursuant to CPL 330.20.
Adjudged that the petition is denied and the proceeding is dismissed, without costs or disbursements.
“Because of its extraordinary nature, prohibition is available only where there is a clear legal right, and then only when a court—in cases where judicial authority is challenged—acts or threatens to act either without jurisdiction or in excess of its authorized powers” (Matter of Holtzman v Goldman, 71 NY2d 564, 569 [1988]; see Matter of Rush v Mordue, 68 NY2d 348, 352 [1986]). Similarly, the extraordinary remedy of mandamus will lie only to compel the performance of a ministerial act and only *595when there exists a clear legal right to the relief sought (see Matter of Legal Aid Socy. of Sullivan County v Scheinman, 53 NY2d 12, 16 [1981]).
The petitioners have failed to demonstrate a clear legal right to the relief sought. Florio, J.P., Fisher, Carni and McCarthy, JJ., concur.