In a highly fact-specific case, the petitioner claimed ineffective assistance of counsel by failing to investigate his mental health history (and thus denying him an insanity defense in his 1993 murder case) and sought to excuse his late assertion of the claim on the theory that it amounted to a claim of actual innocence. The court concluded that even the actual innocence gateway for late claims under AEDPA requires a due diligence predicate, which petitioner had not met. The psychologist’s declaration opined that petitioner’s brain damage (resulting from a car accident before the crime) made him less able to conform his conduct to that required by law. However, there was contrary evidence from other experts on this point at trial.