Michael Pollanen was consulted. If a person drowns in water that contains diatoms, the organisms can often be extracted from the femoral bone marrow and matched to those living in a particular stretch of water. Pollanen's tests established the place of drowning and proved that Walker's leather shoes and wallet had recently been submerged in that same section of river. Guilty as charged. Pollanen almost bounces.
Forensic pathology is at a cusp.
We have to apply serious scientific study. And in the process, one woman attains a measure of dignity in her death.