A more thorough explanation:

ANTI-JOHN LAW

An anti-john law is a criminal-law statute that punishes people who pay for sex with prostitutes.

• In some states, if a person is caught paying for sex with a prostitute, they can be charged with a crime under the anti-john law.
• Anti-john laws are often used to target the demand for prostitution, rather than the supply.

The examples illustrate that an anti-john law is a legal measure that aims to deter people from paying for sex with prostitutes. These laws are designed to reduce the demand for prostitution by punishing those who seek out these services. By targeting the demand side of the industry, anti-john laws aim to reduce the prevalence of prostitution and the associated harms that come with it.