Evidentiary Hearings. If the petitioner has “failed to develop the factual basis of a claim in State court proceedings,” the district court cannot hold an evidentiary hearing unless the petitioner shows that: (1) the claim relies on either (a) “a new rule of constitutional law, made retroactive to cases on collateral review by the Supreme Court, that was previously unavailable,” or (b) “a factual predicate that could not have been previously discovered through the exercise of due diligence;” and (2) “the facts underlying the claim would be sufficient to establish by clear and convincing evidence that but for constitutional error, no reasonable factfinder would have found the applicant guilty of the underlying offense.” If, however, the facts are still not developed despite the petitioner's diligence in state proceedings, then the petitioner does not need to fulfill the requirements of § 2254(e)(2) because the petitioner is not considered to have “failed to develop” the facts.

When a federal court grants an evidentiary hearing, the court may appoint a federal magistrate judge to conduct the hearing. Parties must file written objections within fourteen days of being served with the magistrate's findings in order to preserve the right of review. The district court will then consider the parties' objections and may accept, reject, or modify any part of the magistrate's report.