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Detectives & Spies: the worlds of investigation and intelligence

When it comes to fighting serious and organised crime in the UK, our police officers take their cues from two intriguing worlds: that of the detective and that of the spy (or to put it in more colourful terms: the worlds of Sherlock Holmes and of James Bond).

Police forces have long had criminal investigation departments staffed by detectives. Many forces also have employees that could be crudely termed “spies”, or at least as intelligence analysts or officers working undercover to combat serious crime and threats to public order.

But what exactly are the differences between the detective who “investigates” and the spy who gathers “intelligence”? What are the methods used by each figure? And how do modern police forces use both approaches to fight crime?

Detectives: the investigating officers

Detectives hold a special place in our imagination. From classic fictional sleuths like Holmes and Poirot, to the latest police procedural dramas, we never tire of watching the detective outsmart the criminal. Detective work as a police profession is a relatively recent development though. When modern police forces first appeared in the early 19th century, the idea of specialised detective teams didn’t immediately occur to their leaders. Scotland Yard only got its first detective branch in 1848, nearly two decades after the founding of the Metropolitan Police.

The main methods of criminal investigation are largely unchanged since those early days: interviewing of witnesses, interrogation of suspects, gathering of evidence and forensic analysis of crime scenes. Methods have, however, improved (you can read our previous blog post about the ‘father of forensics’, Alphonse Bertillon, to learn how crime scene investigation started). Investigation today is a rigorous scientific procedure, solving crimes using deductive techniques like the famous hunt for “motive, means and opportunity” when identifying suspects.

Today’s detective branches trace their roots to 1878, the year London’s team was officially reorganised into the ‘Criminal Investigation Department’ (CID), becoming the model for detective units across Britain. The new CID soon found itself in the middle of the Jack the Ripper investigation, its most famous unsolved case. This, along with several other early failures, caused some people to question the role of detectives in UK policing. There was suspicion of these new officers, for where regular “Bobbies” were clearly identifiable as they pounded the streets in their uniforms, detectives in plain clothes seemed more like spies. There were even press campaigns aimed at abolishing detective branches.

However, the role of the detective in dealing with serious and complex crimes, from murder to fraud, was soon recognised as indispensable. The investigative process is the police force’s main route to solving serious crimes that take place across the UK. But the police also have a role in trying to prevent such crimes from taking place at all. And to fulfil this role, they have indeed learned from the world of spying and espionage; from the UK’s intelligence agencies.

Spies and secret agents: the intelligence officers

Intelligence agencies also work to combat threats to citizens, but the sort of threats they fight differ from those that detectives work on. Most intelligence is gathered to protect citizens not from criminal but rather from national security threats. These might include threats from hostile countries or from international terrorism. Today, there are three UK spy agencies which combat such threats: MI5 (countering terrorism and foreign plots); MI6 (spying around the world to gather information on foreign adversaries); and GCHQ (which spies using electronic eavesdropping).

The spies who work for these agencies differ from detectives mainly in the methods they use. The popular image of the “secret agent” like 007 does have some basis in fact. Spies- unlike detectives- do usually work anonymously undercover. They gather “intelligence” rather than “investigate” incidents. And yes, there is a difference.

While “investigations” tend to look back at an event that has already taken place, “intelligence” tends to look forward to imagine what might take place given the right circumstances. “Investigations” are about finding hard facts about something that has happened in order to prove it, whereas “intelligence” is about assessing a range of information to form assumptions about what is most likely to be the case, without any need to prove anything. Because “investigations” are usually part of legal proceedings where findings will be presented to a court in order to enforce whatever law may have been broken, whereas “intelligence” can be (and mostly is) used outside law enforcement, to gather information about foreign nations or businesses, with findings being presented to government ministers for use in making foreign or economic policy.

Intelligence is simply “information” relevant for making good decisions, not a process of identifying, apprehending and convicting criminals. Spies differ most clearly from detectives because they are not law enforcers, and do not have expertise in proving culpability. British spies do not have powers to arrest or bring criminal charges, but simply try to find out “what is going on” and “what might happen”. Indeed, when they suspect a law is being broken (a terrorist plot to murder being prepared, for example) they inform the police whose job it is to arrest, gather evidence, and recommend prosecution.

Yet it’s this very focus on the future and attempting to stop unwanted events from taking place, that police officers have learned from. There is now a lot of cooperation between spy agencies and the police regarding terrorism. But police have long noted that intelligence could be a useful tool in combating wider criminal enterprises. Organised crime groups are, after all, ongoing threats, with planned future crimes being as big an issue as those already committed. But because serious crimes- including drug and financial crime- are law enforcement matters, they fall outside the remit of spy agencies. Thus, it has been up to the police to learn from the spy agencies to create their own brand of “criminal intelligence” services.

Undercover Police: learning from the spies

Most police forces today have developed covert policing units to mount surveillance on so-called “career criminals” and to work undercover infiltrating groups seen as a threat to public order. These might include anarchist and fascist groups, but also protest groups that use direct- or militant- action (like some radical animal rights groups). The tactics have not been without controversy, and there is currently an inquiry taking place into how undercover police officers have spied on some legitimate campaign groups.

Covert police units generally act separately to CID, the skills they use being more spy-like than detective-like. Indeed, in the mid-1990s it was briefly thought that the intelligence agency, MI5, might take on the role of gathering criminal intelligence in addition to its national security work, infiltrating organised crime groups as they do terrorist cells. This would have made them similar to their American counterpart, the FBI, which serves both as the USA’s intelligence service for national security matters and as its premier law enforcement agency. The plans for MI5 did not go so far as to give agents the power to arrest suspects as some FBI agents can. That power remained with the police whose job it was to request intelligence assistance from MI5 when needed.

The experiment did not last long, however. British governments have always liked to keep a distinction between the security services and law enforcement, suspicious of the potential for the rise of a “secret police” with too much power. The gathering of criminal intelligence was thus passed to services which have now become part of the UK’s National Crime Agency (NCA) formed in 2012. The NCA is Britain’s “national police force” which uses both investigative and intelligence techniques to combat serious and organised crime.

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