A top-ranking Brooklyn prosecutor on Monday rejected allegations of misconduct from a man trying to undo his 2005 murder conviction.

John Giuca alleges Anna-Sigga Nicolazzi, now chief of trials in the Brooklyn District Attorney Office’s Homicide Bureau, suppressed information favorable to the defense and relied on false and misleading testimony from an informant to secure Giuca’s conviction for the high-profile slaying of college student Mark Fisher.