The Supreme Court ruled on Wednesday that public sector workers cannot be required to chip in to the unions that represent them. The 5-4 ruling in Janus v. AFSCME deals a devastating blow to the labor movement and one of its most critical sources of funding. Justice Samuel Alito, writing for the majority, said that charging these fees “violates the free speech rights of nonmembers by compelling them to subsidize private speech on matters of substantial public concern.” Union leaders feared that the court would weaken labor with its decision.