JEFFERSON CITY, Mo. — The Missouri Supreme Court overturned 30 years of precedent with a ruling Tuesday that gives greater legal protections to injured workers who subsequently are fired from their jobs. In a 5-2 decision, the Supreme Court ruled that employees no longer have to prove that workers’ compensation claims were the exclusive cause for their dismissal in order to win lawsuits alleging retaliation. Instead, the court said employees must show only that workers’ compensation claims were a …