In Thomas v. U.S., No. 06-15651 (June 30, 2009), the Court held that the "law of the case" doctrine did not preclude a federal inmate, in a § 2255 proceeding, from raising a claim of (1) ineffective assistance of counsel, and (2) infirmity of a prior state convictions which called into question his "career offender" status.
The Court noted that the "law of the case" doctrine only precludes relitigation of issues the were decided explicitly, or by necessary implication, in a prior appeal. The doctrine does not preclude consideration of matters that could have been, but were not, resolved in earlier proceedings.
Thomas had lost a prior appeal of his conviction and sentence, after his counsel filed an Anders brief and he filed a pro se brief. However, the ineffective assistance issue was not raised on direct appeal. Similarly, the invalid state court conviction was not presented on appeal, neither in the Anders brief nor in the pro se brief. Consequently, these two issues were not precluded from § 2255 consideration.