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.
[1] In the legal system, discretion is often defined as the ability of a judge to choose where, how and with what severity to sentence a person who has been convicted.
They have to use discretion to weigh the rights of the accused, the feelings of the victim, and the capacity of prisons when determining a proper punishment.
Prosecutors control plea bargains and thus have possibly the most discretion-based role in the criminal justice process.
[3] An abuse of discretion can be defined as "a failure to take into proper consideration the facts and law relating to a particular matter; an arbitrary or unreasonable departure from precedent and settled judicial custom.