What deference, if any, is due to a state court decision on an exhausted post-conviction claim when the decision arises from a system that does not give the petitioner a full and fair opportunity to litigate the claim and the federal courts do not give the petitioner a chance to cure default, but consider such a claim adjudicated on the merits?

QUESTION PRESENTED What deference, if any, is due to a state court decision on an exhausted post-conviction claim when the decision arises from a system that does not give the petitioner a full and fair opportunity to litigate the claim and the federal courts do not give the petitioner a chance to cure default, but consider such a claim adjudicated on the merits? i