Does Hikida Create a Change in the Law of Apportionment?

• Publication year: 2019
• Author: Ray Stanek, Esq. Concord, California

Does Hikida Create a Change in the Law of Apportionment?

Ray Stanek, Esq. Concord, California

The recent case of Hikida v. WCAB (2017) 12 Cal. App.5th 1249 presents an interesting question as to whether the decision has weakened the rules of apportionment in the California workers' compensation system. This article lays out the history of apportionment law, in particular Labor Code section 4663, leading up to the Hikida decision and examines subsequent cases for signs of any emerging, and durable, trends from Hikida.

A Brief History of Apportionment in California Workers' Compensation

Apportionment Before SB 899

Apportionment of permanent disability (PD) has always been a difficult endeavor for the defense practitioner. Prior to 2004, three Labor Code sections governed apportionment.

Former Labor Code section 4750 provided apportionment for disability that resulted from a prior injury the applicant had sustained. Former Labor Code section 4750.5 stated that an employee who has sustained a compensable injury and subsequently sustains an unrelated, noncompensable injury should not receive PD indemnity for any PD the subsequent noncompensable injury had solely caused. Former Labor Code section 4663 pertained to cases relating to an aggravation of any disease existing prior to a compensable injury. According to that section, compensation was proportionate only to the disability due to the aggravation of the prior disease that is reasonably attributed to the injury.

Impact of Passage of SB 899

In 2004 the Legislature enacted SB 899, game-changing legislation regarding the rules of apportionment. This statute repealed all former apportionment statutes. In their place, the Legislature enacted two new apportionment statutes: Labor Code sections 4663 and 4664.

Labor Code section 4663 allowed, for the first time, apportionment of PD to causation. The doctor was now entrusted to make an apportionment determination by finding the approximate percentage of the PD caused as a direct result of industrial injury and the approximate percentage other factors had caused both before and after the industrial injury.

Furthermore, Labor Code section 4664 states that the employer shall be liable only for the percentage of PD the industrial injury directly caused. If the applicant has received a prior award of PD, it should be conclusively presumed that the prior award of PD existed at the time of the subsequent industrial injury.

The Seminal Case on Apportionment: Escobedo

Escobedo v. Marshalls (2005) 70 Cal.Comp.Cases 604 (en banc) held that apportionment should be based on causation of the PD and not on causation of the injury. The case established that the applicant has the burden of establishing that industrial injury directly caused the PD and that the defendant has the burden of establishing the percentage of disability other factors...