It always interests me when a convicted defendant wins a habeas corpus petition. It means he was found guilty in a state court of a crime but the conviction was unconstitutional. It often takes a federal court years later to find the conviction was unconstitutional. Same case, contrary results in different courts.
The case is Lewis v. Connecticut, decided on May 14. Lewis was convicted of murder solely on the testimony of Ruiz. But unknown to Lewis, Ruiz had repeatedly denied knowledge of the murders and implicated Lewis only because the police promised to let him go if he admitted being the getaway driver and implicated Lewis and someone else. Lewis did not know this because, in violation of Brady v. Maryland, the prosecution did not turn over this information to his lawyer prior to the criminal trial. (This information about Ruiz came out a few years after Lewis was convicted, during a court hearing that challenged the conviction of Lewis's co-defendant).
The district court granted Lewis's pro se habeas petition, and the Court of Appeals (Walker, Winter and Cabranes) affirms. The state court conviction violated clearly-established Supreme Court authority. Brady is a Supreme Court ruling from the 1960s. As you probably know from the movie My Cousin Vinny, the prosecution has to turn over all evidence favorable to defendant even if the defendant does not ask for it. So the law was clearly established. While the state court in affirming Lewis's conviction said that all exculpatory information was revealed to him prior to trial, the Court of Appeals says this was simply not true. The good stuff from Ruiz was not turned over to Lewis.
In the end, this information about the nature of Ruiz's involvement in the case would have made a difference at Lewis's trial. Ruiz was the state's key witness at trial. What jury would believe his account if it knew the truth about Ruiz's account, that he was promised a break if his implicated Lewis, especially since Ruiz told the police he knew nothing about the murder? This would have made for great impeachment material at trial. As the Court of Appeals says, this information constituted "credible evidence that Ruiz simply parroted information supplied by an unscrupulous police officer" and it "undermines Ruiz's credibility and thus any reasonable confidence in the outcome of the trial."