crack down

take strict action to stop something illegal or wrong

B2

What does "crack down on sth" mean?

To crack down on something means that a person in authority, or an organisation like a government or police force, takes firm and serious action to stop illegal or unacceptable behaviour. The focus is on enforcement — stricter rules, more inspections, heavier penalties, or increased policing. It strongly suggests that the behaviour was previously tolerated or not dealt with effectively enough, and that something is now changing. You will hear and read this phrasal verb constantly in news reports and political speeches, often used alongside words like 'crime', 'corruption', or 'fraud'. It works equally well in spoken conversation and formal writing, so it is a highly versatile item to have in your vocabulary.

Examples

How to use it

authority / institution + crack down on + behaviour or crime

This is the core pattern: an authority figure or institution takes action against a specific type of illegal or unacceptable activity.

The city council is cracking down on illegal parking in the town centre.

crack down on + group defined by illegal activity

The object can be a group of people, provided the group is defined by their involvement in wrongdoing rather than identified as specific named individuals.

Border agencies have been cracking down on smugglers operating along the coast.

crack down on + pronoun (it / them)

When the target has already been mentioned, a pronoun naturally replaces the noun after 'on'.

Benefit fraud is a serious problem, and the government has decided to crack down on it.

crack down (without object)

When the context makes the target obvious, 'crack down' can be used without 'on' and a specific object.

After several accidents on that road, the police announced they would crack down.

crackdown on + noun (noun form)

The related noun 'crackdown' is one word and is especially common in headlines and news writing as an alternative to the phrasal verb.

The new crackdown on money laundering has led to dozens of arrests.

Common Collocations

crimecorruptiontax evasiondrug traffickingillegal immigrationspeeding

Common Mistakes

Wrong preposition after 'crack down'

Learners sometimes use 'against' or 'about' instead of 'on'. The correct preposition is always 'on', which directly introduces the target.

✗ The authorities decided to crack down against tax evasion.
✓ The authorities decided to crack down on tax evasion.
Confusing 'crack down on' with 'come down on'

'Come down on' is used when you are criticising or punishing a specific person, while 'crack down on' targets a type of behaviour, crime, or group engaged in wrongdoing — not a named individual.

✗ The manager cracked down on Sarah for missing the deadline.
✓ The manager came down on Sarah for missing the deadline. / The manager cracked down on late submissions.
Inserting words between the parts of the phrasal verb

'Crack down on' is a fixed three-part unit and cannot be separated — nothing should be placed between 'crack', 'down', and 'on'.

✗ The police cracked on drug dealers down.
✓ The police cracked down on drug dealers.

Usage

This phrasal verb is neutral in register and works in both spoken and written English. It is especially common in news and political contexts. The related noun 'crackdown' (one word) is also very useful: 'a crackdown on corruption'.

Frequently Asked Questions

Can 'crack down on' be used in the passive, like 'fraud is being cracked down on'?

Technically it is possible, but native speakers almost always avoid it because it sounds clunky. Sentences like 'fraud is being cracked down on by authorities' feel awkward in both speech and writing. It is much more natural to keep the verb active: 'Authorities are cracking down on fraud.'

What kinds of things can follow 'crack down on'?

The object is almost always a type of illegal or socially unacceptable behaviour — things like corruption, speeding, fraud, or tax evasion — or a group defined by involvement in that behaviour, such as gangs or traffickers. It would sound unusual to use 'crack down on' with a positive or neutral activity.

Does 'crack down on' always need an authority or official institution as the subject?

It is most naturally used with subjects like governments, police forces, or regulators, and this is by far the most common pattern. However, in informal speech, you might hear it used with other subjects, such as a school or manager taking strict action. The association with official enforcement is strong, though not absolute.

What is the difference between 'crack down on' and 'clamp down on'?

The two are nearly synonymous and interchangeable in most situations. 'Crack down on' is slightly more common and tends to emphasise active enforcement, while 'clamp down on' can lean a little more towards the idea of applying restrictions or controls. In everyday use, the difference is minimal.

Is 'crackdown' (one word) related to this phrasal verb, and can I use it the same way?

Yes — 'crackdown' is the noun form of 'crack down on' and is extremely common, especially in news headlines. You can say 'a crackdown on corruption' in place of 'cracking down on corruption'. The noun form often feels more concise in written contexts.

Related Phrasal Verbs

clamp down on sth

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