Exhaustion Requirement. Habeas relief generally is not available unless the petitioner has “exhausted the remedies available” in state courts, which means using all procedures available under state law to raise the claim and properly pursuing a claim through the entire appellate process of the state. The exhaustion doctrine requires that the petitioner present the substance of the claim to the state courts to give those courts a fair “opportunity to apply controlling legal principles to the facts bearing upon [the petitioner's] constitutional claim.” To meet the exhaustion requirement, a habeas petitioner must present material to a state court, which alerts the court to the presence of a federal claim. The petitioner may be able to satisfy this requirement even if the state court has not addressed the claim in a written opinion. In some instances, a state supreme court's refusal to rule for invalid prudential or procedural reasons on a petitioner's claim will be construed by the federal habeas court as exhaustion of the claim. The burden of proving that a federal habeas claim has been exhausted lies with the petitioner.

The state can waive the exhaustion requirement. However, “[a] State shall not be deemed to have waived the exhaustion requirement ... unless the State, through counsel, expressly waives the requirement.” Although courts generally may not grant an application for a writ of habeas corpus based on unexhausted claims, courts may deny such applications on the merits, even though the petitioner failed to exhaust available state remedies.

Courts may dispense with the exhaustion requirement if further state litigation would be futile or in other exceptional circumstances, such as when the petitioner's federal claim is clearly without merit or if a miscarriage of justice has occurred. Additionally, federal courts may waive the exhaustion requirement if a death row petitioner's execution appears imminent, and the state court declines a stay of execution despite continued litigation of federal constitutional claims in state court.

Federal courts may consider habeas petitions containing both exhausted and unexhausted claims (“mixed petitions”) and may deny unexhausted claims on their merits. If a federal court does not consider a mixed petition, a state prisoner may either (1) return to state courts to litigate the unexhausted claims so they can then be presented together in a single petition, or (2) amend the habeas petition to present only exhausted claims to the federal district court. The federal court may grant a petitioner a continuance to pursue unexhausted claims in state court, but it is not required to do so.

After the passage of the Antiterrorism and Effective Death Penalty Act of 1996 (AEDPA), which imposes a one-year limitation period to apply for a writ of habeas corpus, a petitioner whose mixed petition is dismissed may find the claims time- barred when attempting to return to federal court. District courts are not required to warn petitioners that their federal claims would be time-barred from federal court review if the AEDPA limitation period expires while they are exhausting their remedies.