The case is Dillon v. Conway, decided on April 26. After he was convicted of murder, assault, attempted robbery and criminal possession of a weapon, Dillon hired a lawyer to file the habeas action. After exhausting his state court appeals, the conviction became final on November 29, 2006, which gave Dillon until November 29, 2007 to file his petition in federal court. (There's a one-year statute of limitations for habeas corpus petitions). Dillon's lawyer, Langone, filed it in federal court on November 30, and the district court threw out the petition. The Court of Appeals (Cabranes, Lohier and Winter) reverses.
The Supreme Court says the deadline for these petitions is flexible, "subject to equitable tolling in appropriate cases." This exception applies if the inmate "has been pursuing his rights diligently and some extraordinary circumstance stood in his way and prevented timely filing." The "extraordinary circumstance" test makes this an uphill battle in most cases, but the Second Circuit says that Dillon satisfies it, though it regards this as a close case.
Here's why. First, Dillon was certainly pursuing his rights, repeatedly pressuring his lawyer to file the petition and specifically urging him not to wait until the last minute. He relied on his lawyer's assurance that the petition would be filed well in advance of the deadline.
Second, Dillon's lawyer's negligence constitutes an extraordinary circumstance. The lawyer thought that the petition was due one year and one day after the state court conviction became final. He held this belief because he misread a 1998 federal decision that applied that deadline in a different context; counsel knew this case well, as he was a paralegal for one of the law firms that worked on the case. The Court of Appeals observes,
although miscalculating a deadline is the sort of garden variety attorney error that cannot on its own rise to the level of extraordinary circumstances, Dillon's case involves more than a simple miscalculation. Langone in effect admitted affirmatively and knowing misleading Dillon by promising him that he would file the petition before November 30, 2007. Langone breached that promise when he failed to follow his client's instruction, with disastrous consequences that Dillon could neither have foreseen nor prevented.