If Paul Stine was of healthy disposition and had no underlying health issues, the multiple parenchymal hemorrhages causing blood to leak into the tissues of the lungs and creating congestion in the dependent portions, can be found in patients with chest trauma. An impact to the chest from such things as the steering wheel can cause parenchymal hemorrhage without injury to the sternum and ribs. "A pulmonary contusion is a bruise on the lung parenchyma. Pulmonary contusion is reported to be present in 23% of patients with significant blunt chest trauma, and occurs most often from automobile collisions with rapid deceleration. Regardless of the mechanism, injury to the lung results in injury to capillaries and the leaking of blood into the lung tissue and alveoli. This collection of fluid in the alveoli interferes with normal alveolar-capillary gas exchange". link. "Chest wall and pulmonary injuries caused by blunt thoracic trauma include many organs, tissues and systems. The age of the patient is important when evaluating a blunt chest trauma. While a trauma in the pediatric age group may not cause a chest wall injury due to bone elasticity, it may lead to serious complications and even death in the elderly population.The best example of acceleration-deceleration damage is motor vehicle accident. The most common condition is the sudden and high-speed deceleration of the anterior thorax, resulting in injury to the vascular structures, bones, soft tissues and organs. At the same time, the presence of steering wheel deformity caused by the driver hitting the steering wheel increases thoracic injuries, complications and mortality" .link..
It is without doubt that Paul Stine died as a result of one shot to the right side of his head causing massive brain injury, but what occurred during the taxicab journey from the Union Square plaza in San Francisco to the intersection of Washington and Cherry Streets in Presidio Heights? It is unknown when the Zodiac Killer pulled the gun on Paul Stine, despite the common portrayal of a surprise attack occurring during the very last seconds of the trip.
To sum up the autopsy, the bullet entered just in front of the right ear, traveled at a shallow angle anteriorally and struck the left temporalis muscle (used in chewing). Without knowing the head position of Paul Stine at the moment the gun was fired, makes it impossible to determine where the killer was seated in the taxicab when he delivered the fatal shot. The parenchymal hemorrhages to the lungs of Paul Stine (if not present prior to the taxicab journey) warrants an answer to the possible events that occurred within the taxicab during his final journey on October 11th 1969. The story is not complete.