This is an important case for a number of reasons. The first is historical: Storch was one of the most infamous jailhouse snitches in the Los Angeles County Jail during the 1980s, a period in which jailhouse snitch fabrication was rampant, numerous wrongful convictions occurred, and which eventually triggered a massive Grand Jury investigation and stringent reforms in Los Angeles.
The factual basis for the decision is also important. Appellate courts rarely conclude as a factual matter that a witness such as a jailhouse informant committed perjury, which is one of the reasons it is so difficult to overturn a conviction even after a witness recants. See previous post: In the news-- Recantation. In this case, the Ninth Circuit decided that "it was objectively unreasonable for the Superior Court to find that Storch testified truthfully at the 1984 trial," based on Storch's history as an informant and his other lies at trial. From the opinion:
There is simply too much evidence of Storch's pattern of perjury to conclude otherwise. At the time of Maxwell's trial, Storch was already employing the "booking" formula that he would later teach others and for which he would become famous; the housing records show that Storch had physical proximity to Maxwell; Storch openly admitted that he was in possession of a newspaper article about the murders; the newspaper article itself mentioned all of the specific facts to which Storch testified--namely, that the police had found Maxwell's palm print on a nearby park bench; and, finally, Storch contacted Deputy District Attorney Sterling Norris with the news of his cellmate's spontaneous confession and negotiated his own deal in exchange for his testimony.In other words, it was just too likely that Storch was lying for the government to use him. As our knowledge of jailhouse informants increases, there may be more informants who fit this too-unreliable-to-testify profile.
Finally, the case has doctrinal significance. The court held that the use of Storch at trial violated Maxwell's due process rights. This was in large part because Storch was the "'make-or-break' witness for the state" and "the centerpiece of the prosecution's case" and therefore his testimony was clearly material to the outcome of the trial. Notably, the court assumed for the sake of argument that the government did not know that Storch was lying -- the due process violation flowed not from any intentional government misconduct, but because "to permit a conviction based on uncorrected false material evidence to stand is a violation of a defendant's due process rights." This is an important rule -- it is not uncommon for defendants to discover post-trial evidence that a key informant witnesses lied--either because of recantations or other impeachment evidence. See for example this post: More on the Spokane convictions. The Maxwell decision suggests that courts may be starting to take such evidence of informant perjury more seriously.