Collateral Source Rule

Tort damages are designed to be compensatory in nature and make a party whole. The collateral source rule is an exception to this rule. It provides that a wrongdoer is not entitled to have the damages to which he/she is liable reduced by the fact that plaintiff has received or will receive compensation or indemnity for the loss from a collateral source. Washington By Washington v. Barnes Hosp., 897 S.W.2d 611, 619 (Mo. 1995). The reasoning is that the wrongdoer should not benefit by separate, collateral payments made to the person he/she has wronged. 
Missouri has applied the collateral source rule in many different circumstances: workers’ compensation benefits, disability pension benefits, retirement benefits, employer’s medical plan, and sick leave. Most commonly, Missouri courts apply the collateral source rule to prevent defendants from informing juries of insurances policies contracted for and paid for by plaintiffs. See Iseminger v. Holden, 544 S.W.2d 550, 553 (Mo. 1976).