This lesson trains 25 C2 idioms on Crime, Law & Rules. Idioms signal fluency when used naturally — forcing them into every sentence hurts your score. Practise in the runner first, then revisit every expression in the glossary. Review mode after completion shows how each idiom fits its context.
tow the line
Obey rules or authority.
While taking part in a debate about rules and punishment, the speaker highlighted “tow the line”, which means “Obey rules or authority”.
[be/live] in a dream world
Have unrealistic hopes or beliefs.
In a conversation about crime and justice, “[be/live] in a dream world” was explained as an expression meaning “Have unrealistic hopes or beliefs”.
uncharted [territory/waters]
An unknown area of experience.
During a courtroom discussion, the trainer referred to “uncharted [territory/waters]”, a useful expression for the idea “An unknown area of experience”.
footloose and fancy-free
Free and without responsibilities or commitments.
In a debate about rules and punishment, “footloose and fancy-free” was explained as an expression meaning “Free and without responsibilities or commitments”.
look on the bright side
Try to see the positive part of a bad situation.
During a debate about rules and punishment, the facilitator introduced “look on the bright side”, an expression meaning “Try to see the positive part of a bad situation”.
hindsight is a wonderful thing
It is easy to judge after knowing what happened.
In a courtroom discussion, participants used “hindsight is a wonderful thing” to communicate this idea: “It is easy to judge after knowing what happened”.
truth will out
The truth will eventually become known.
In a legal-studies class, participants used “truth will out” to communicate this idea: “The truth will eventually become known”.
plead the fifth
Use the US constitutional right not to answer a question that may incriminate you.
In a conversation about crime and justice, participants used “plead the fifth” to communicate this idea: “Use the US constitutional right not to answer a question that may incriminate you”.
that's a turn-up for the books
That is a surprising or unexpected event.
While taking part in a conversation about crime and justice, the speaker highlighted “that's a turn-up for the books”, which means “That is a surprising or unexpected event”.
fall foul of
Break rules or come into conflict with.
During a conversation about crime and justice, the facilitator introduced “fall foul of”, an expression meaning “Break rules or come into conflict with”.
do a runner
Run away to avoid a difficult situation.
During a courtroom discussion, the trainer referred to “do a runner”, a useful expression for the idea “Run away to avoid a difficult situation”.
[someone's] hands are tied
Someone is unable to act because of rules or circumstances.
In a courtroom discussion, “[someone's] hands are tied” was explained as an expression meaning “Someone is unable to act because of rules or circumstances”.
be on the fiddle
Be getting money dishonestly.
While taking part in a debate about rules and punishment, the speaker highlighted “be on the fiddle”, which means “Be getting money dishonestly”.
the plot thickens
The situation becomes more complicated or mysterious.
During a legal-studies class, the trainer referred to “the plot thickens”, a useful expression for the idea “The situation becomes more complicated or mysterious”.
to cap it all
In addition to everything else, especially something bad.
During a courtroom discussion, the facilitator introduced “to cap it all”, an expression meaning “In addition to everything else, especially something bad”.
toe the line
Obey rules or authority.
In a conversation about crime and justice, “toe the line” was explained as an expression meaning “Obey rules or authority”.
more by luck than judgement
Mostly because of luck, not skill.
While taking part in a courtroom discussion, the speaker highlighted “more by luck than judgement”, which means “Mostly because of luck, not skill”.
hang fire
Delay making a decision.
While taking part in a legal-studies class, the speaker highlighted “hang fire”, which means “Delay making a decision”.
poacher turned gamekeeper
A former wrongdoer now working against such wrongdoing.
During a debate about rules and punishment, the trainer referred to “poacher turned gamekeeper”, a useful expression for the idea “A former wrongdoer now working against such wrongdoing”.
it's easy to be wise after the event
It is easy to judge after knowing the result.
During a conversation about crime and justice, the trainer referred to “it's easy to be wise after the event”, a useful expression for the idea “It is easy to judge after knowing the result”.
pull the wool over [someone's] eyes
Deceive someone.
During a legal-studies class, the facilitator introduced “pull the wool over [someone's] eyes”, an expression meaning “Deceive someone”.
might as well be hung for a sheep as a lamb
If you will be punished anyway, you may as well do the bigger thing.
In a legal-studies class, “might as well be hung for a sheep as a lamb” was explained as an expression meaning “If you will be punished anyway, you may as well do the bigger thing”.
a short sharp shock
A brief, severe punishment meant to correct behaviour.
During a courtroom discussion, the facilitator introduced “a short sharp shock”, an expression meaning “A brief, severe punishment meant to correct behaviour”.
the boys in blue
The police.
In a debate about rules and punishment, participants used “the boys in blue” to communicate this idea: “The police”.
bring to book
Make someone answer for a crime or wrongdoing.
In a legal-studies class, participants used “bring to book” to communicate this idea: “Make someone answer for a crime or wrongdoing”.