Kopping

The question here is whether the presumption established by subdivision (b) of Labor Code section 4664 (section 4664(b)) is conclusive or rebuttable. That statute, which is one of the workers’ compensation statutes enacted in 2004 to govern apportionment of permanent disability (Stats. 2004, ch. 34, § 35), provides that “[i]f the applicant has received a prior award of permanent disability, it shall be conclusively presumed that the prior permanent disability exists at the time of any subsequent industrial injury. This presumption is a presumption affecting the burden of proof.”

Petitioner Ed Kopping contends this statute is internally inconsistent, because the second sentence means the section 4664(b) presumption is actually rebuttable, not conclusive as the first sentence says it is. Kopping contends the statute must be construed liberally in his favor and thus interpreted to create a rebuttable presumption of the continued existence of a prior permanent disability that can be rebutted by proof of medical rehabilitation prior to the subsequent industrial injury.

For reasons we will explain, we conclude the Legislature intended the section 4664(b) presumption to be…