First question – how could the officer tell how you were wearing your shoulder harness, if you were driving? Did he have probable cause to pull you over for any reason, or was it a spot check looking for violations? That’s your first line of defense. Second question – were you wearing a lap belt across your seat at the time? Most shoulder harnesses come with seat belts attached. What does your State law require, a seat belt, or a seat belt and a shoulder harness if equipped with one? And does the State law dictate how it is to be worn, and if so, specifically over the shoulder or as recommended by the manufacturer? Third line of defense.
It is known fact from first responders that wearing the shoulder harness over the shoulder, as opposed to under, can cause severe injuries in an accident, including fractured color bone and ribs, compression of the chest cavity, and even death. Since learning that, I always wear the shoulder belt under my arm. Especially for your height, you are prudent to wear it under your arm in your own best interests. Fourth defense. Can a law that requires compliance with a manufacturer’s “recommendations” be enforced if it puts you at risk? I would argue that the manufacturer’s recommendations are that only, leaving the user with discretion according to each individual situation. In the future, two options: (1) sit on a cushion to raise you up, for better visibility as well, or (2) get someone to lower the shoulder strap retainer further down on the door jam. Easier to sit on a cushion.