Discretion has the meaning of acting on one's own authority and judgement. In law, discretion as to legal rulings, such as whether evidence is excluded at a trial, may be exercised by a judge. Some view discretion negatively, while some view it positively. Discretion is at all levels of law enforcement.
Those in a position of power are most often able to exercise discretion as to how they will apply or exercise that power.
The ability to make decisions which represent a responsible choice and for which an understanding of what is lawful, right or wise may be presupposed. See Websters Third New International Dictionary (unabridged).
In the legal system, discretion is often defined as the ability to choose where, how and with what severity to act. A person chooses to utilize his or her options and decides which to use, whether this is arresting a person on the street (criminal) or evicting someone from an apartment (civil) or anywhere in between. There are some arguments that implementing discretion overrules or weakens the rule of law. However, laws cannot be written without using discretion and therefore the rule of law serves to guide discretion towards societal expectations, norms and, at least in part, public interest
The term "Crime is defined as an action that is by law, banned or restricted and enforced via Punishment. But, where law ends and discretion begins lies in implementing those laws. The enforcers, police officers, are tasked with enforcing these regulations, but they often have the discretion of when to file charges and arrest. For example, a traffic violation, the police officer may simply issue a warning. In fact discretion can be found in all stages of the criminal justice system. The victim, has the discretion to use self defense and to report the crime given the opportunity. The Dispatch officer decides the priority of the call, an officer responding has discretion to take statements from witnesses as well as detain potential suspects. The suspect/the accused has the discretion to obtain a lawyer, how they will plead and to accept a plea bargain. The prosecutor has the choice to prosecute a case or drop the charges as well as suggesting plea bargains. The judge has discretion every time an objection is raised or evidence is given. The jury has discretion over the final verdict. These examples are only a small cross section of the chain of choices that is criminal law.