Florida Judge Ryon McCabe has ruled at a hearing that Ryan Routh, a suspect in the Florida assassination of former President Donald Trump, will remain in custody while his case is heard. The judge found that the evidence presented by prosecutors was sufficient to support the continued detention of Mr. Rouse, who was charged in his initial court appearance with two firearms-related offenses, including possession of a firearm as a convicted felon and possession of an erased serial number.