He who spares the guilty punishes the innocent.

Explanation

(English-origin maxim.) Failure to punish the guilty is itself an injury to the innocent — when wrongdoers go unpunished, their future victims bear the cost of the law's leniency.

Where this applies

• A judge who lets a repeat offender off with a warning effectively punishes the offender's next victim, who could have been protected by proper sentencing.
• A school that refuses to discipline a bully leaves the bullied children to suffer the consequences of the school's leniency.
• A prosecutor who declines to charge a known drunk driver shares responsibility when that driver injures someone in a future accident.