Fourth Department answered this question with a clear "yes."
Petitioner commenced this habeas corpus proceeding contending that the Department of Correctional Services (DOCS) lacked the authority to include a period of postrelease supervision in petitioner's sentence calculation because the sentencing court had not imposed a period of postrelease supervision. County Court erred in refusing to sustain the writ of habeas corpus based upon its conclusion that postrelease supervision was mandated by law and that nullification of postrelease supervision would render petitioner's sentence invalid. As the Court of Appeals has written, "[b]ecause CPL 380.20 and 380.40 collectively provide that only a judge may impose a [postrelease supervision] sentence, we conclude that DOCS may not do so" (Matter of Garner v New York State Dept. of Correctional Servs., ___ NY3d ___, ___ [Apr. 29, 2008]).
Thus, the Court ordered that Sheriff discharge petitioner from custody forthwith.