South West police have warned people who impersonate a police officer will be prosecuted.
The warning comes after a Bunbury man was found guilty of pretending to be a police officer when he tried to "take the law into his own hands".
The 44-year-old pleaded guilty to impersonating a public officer when he faced Bunbury Magistrates Court on Thursday.
South West Supt Peter Hatch said the crime did not happen often but when it did, it was taken seriously.
"If you want to pretend to be a police officer then you will get the attention of a real police officer," he said.
"It's just something you don't do and the community has to have the confidence they are dealing with a real officer."
The man left a message on a voicemail at a Bunbury business on March 3 claiming he was a police officer and the house of an employee had been raided and the employee was a "drug addict".
Magistrate Dianne Scaddan told the man he had committed a breach of trust and a breach of police officer duties.
She said if he was not happy with how something was dealt with by police, it was "not the right way to go about things" and warned the maximum fine for impersonating a police officer was $12,000 and 12 months imprisonment.
But she took into account the man's guilty plea in sentencing, fining him $1500 and ordering he pay costs of $150.80.