The suspect in Long Island’s infamous Gilgo Beach serial killings has lost his bid to separate into multiple trials the sprawling case involving seven brutal killings spanning decades. New York State Supreme Court Justice Timothy Mazzei ruled Tuesday that the trial against Rex Heuermann, a Manhattan architect who lived on Long Island, would move forward as a single trial. “We wanted one and that's what we got,” Suffolk County District Attorney Ray Tierney said after the brief hearing in Riverhead court. Heuermann's lawyers also contended that jurors would struggle with the “volume and complexity” of the evidence in the case if all seven killings were tried together. Prosecutors, in court filings, maintained the state health law cited by Heuermann’s lawyers didn't apply to forensic labs.