Heather Carol Hallett, Baroness Hallett (born 16 December 1949), styled The Rt Hon.
Lady Justice Hallett, is an English judge of the Court of Appeal.
She is the fifth woman to sit in the Court of Appeal after Dame Elizabeth Butler-Sloss (now Baroness Butler-Sloss) (1988), Dame Brenda Hale (now Baroness Hale of Richmond) (1999), Dame Mary Arden (2000) and Dame Janet Smith (2002).