Which person or organization has the most discretion with how the law is applied or interpreted on the scene?

On the scene, law enforcement officers typically have the most discretion in how the law is applied or interpreted. They assess situations in real time, deciding whether to enforce laws, issue warnings, or make arrests based on their judgment and the specifics of the incident. Their decisions can significantly influence the legal process that follows, although their discretion is subject to policies, training, and legal standards.