The History of Private Investigators

private investigators

The History of Private Investigators

When you think of a PI do you imagine a professional sleuth, clad in a trench coat and fedora slumped in a car with a long lens camera peaking out of the window?

You’d be forgiven for thinking this is what a PI looks like.

Pop culture depictions on our TV screens have sold us this image.

They portray investigators as troubled, hardened detectives with a tragic back story. And they’re usually prone to having a drinking problem…

In reality, PIs are much more inconspicuous, fastidious and by the book.

You’d actually be more likely to find a private investigator sipping coffee in a nearby café. He or she might be reviewing research or conducting a discrete meeting. You wouldn’t even know that the person was investigating anything!

So, where did these depictions actually come from? How did the first private investigator really start out?

Early Investigators

The history of private investigations goes right back to the 1700s.

The oldest reported official detectives were set up in 1749 in the UK, known as The Bow Street Runners. They were paid a retainer to deal with the post-war crime wave.

However, Eugène François Vidocq, a French soldier, criminal, and privateer is recognised as the first Private Investigator in history. He founded Le bureau des Renseignements in 1833, a company that was a mix of a detective agency and a private police force.

Over the last 150 years PI’s have been variously known as Inquiry Agents, Private Inquiry Agents, Commercial Agents, Private Detectives, Private Investigators, and of late, Professional Investigators.

There is a whole range of specialist investigators concentrating on a narrow field, such as road traffic collisions, insurance claims, fires and numerous others.

The establishment of investigation agencies is now a norm in most societies, and PI’s can now be found on almost every continent and major city across the world.

The first PI’s were actually considered private police officers. They were a private detective agency for their clients. This was as a result of clients finding the police ill-equipped to handle their concerns.

The first private investigators seemed to operate next to the law. While the contemporary private investigations industry is highly regulated.

While regulated, the private investigations industry is still viewed as a taboo industry.

How do I become a Private Investigator?

Becoming a Private Investigator in Queensland starts with a CPP30619 Certificate III Investigative Services. This qualification is nationally recognised.

Once completed, you can then apply to the Office of Fair Trading for a licence to operate. States other than QLD have different licensing authorities. This process includes a criminal history check and fingerprinting.

The licensing department will determine whether you are a fit and proper person to hold a licence. This is a far cry from the early requirements of a PI!


Private Investigators work with clients in both the public and private sectors. Despite pop culture depictions, you don’t receive a badge or have special powers above those of private citizens. But, investigators do have extensive knowledge of the law and know enough not to break it.

Today, PI’s must understand and follow relevant Commonwealth, State and Territory legislation. This includes privacy, evidence gathering, restrictions on recording devices and surveillance. More recently, the legislation has extended to include the use of drones.

Investigators need creative problem solving skills. They need to have a deep understanding of what they can and can’t do in line with legislation. This kind of work takes ingenuity and keen observation skills.

If you’re interested in knowing more about this fascinating industry you can check out our articles: What do Investigators do? or Becoming a Plaintiff Investigator. Or, have a chat with one of our friendly course advisors today.

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