What does the Last Injury Rule (LIR) establish in a responsibility case?

The Last Injury Rule (LIR) is a principle used in workers' compensation cases to determine which injury is responsible for the worker's claim when multiple injuries are involved. The rule establishes that the last injury that made an independent contribution to the underlying pathology is considered the basis for liability in the case. This means that if an employee suffers multiple injuries, the one that most recently occurred and has had a significant and independent impact on the employee's medical condition will typically be deemed the responsible injury.

In this context, understanding how the Last Injury Rule functions is crucial for claims adjusters, as it helps them evaluate complexities in cases involving multiple injuries. It ensures that the most relevant and causative event leading to a current medical condition is identified and addressed.

This is distinct from other considerations: determining the most severe injury reported would not necessarily correlate to causation of ongoing symptoms, nor does it prioritize the documented timeline of injuries or earlier injuries that might not have contributed significantly to the current condition. These aspects are less relevant under the Last Injury Rule, which specifically targets the injury that has the most significant direct effect on the employee's current state of health.