Mo. Rev. Stat. § 630.950: Immunity from liability, when.

Any department employee or employee of a residential facility, day program, or specialized service operated, funded, or licensed by the department who reports on or discusses employee job performance for the purposes of making employment decisions that affect the safety of consumers and who does so in good faith and without malice shall not be subject to an action for civil damages as a result thereof, and no cause of action shall arise against him or her as a result of his or her conduct pursuant to this section. The attorney general shall defend such persons in any such action or proceeding.