Little thieves are hanged, but great ones escape. proverb
Small-time criminals will face the full consequences of the law while those who commit large-scale crimes will go unpunished.
A: He was sentenced to three years in prison for bank robbery; meanwhile, there are some politicians who accept bribes can get away with punishment. B: I see! Little thieves are hanged, but great ones escape.
A: Little thieves are hanged, but great ones escape. B: Yeah! Sometimes I feel that there's no justice in the world at all.
To punish someone or something harshly
Someone is going to receive a harsh punishment for what he or she has done something wrong.
To punish someone for committing a crime
Prison or jail
If someone has a cast iron stomach, they have a strong stomach that can digest unusual food and even bad food without being ill.
Jimmy must have a cast-iron stomach, when he drank milk with lime juice and felt perfectly fine afterward.