This review examines how mathematical models that predict how drugs and chemicals move through the body could be better used in forensic science to help explain cause of death and interpret toxicology evidence. Currently, only a few such models have been specifically developed for forensic purposes, though many exist for common drugs like opioids, cocaine, and alcohol. A major challenge is accounting for how drug concentrations change after death, which can make it harder to determine what the concentration was when the person died.