A federal court panel revived a First Amendment case brought by a Wisconsin prisoner who charged a prison officer retaliated against him by falsely labeling him a snitch.The 7th U.S. Circuit Court of Appeals last week vacated the decision of a federal magistrate judge who granted summary judgment to the officer, Lynn Koeller. In vacating the summary judgment decision, the federal appeals panel found that the magistrate judge erred by resolving disputed issues of material fact in favor of Koeller.Joshua Howard, a Wisconsin …