The investigation of murder is a huge subject in books, podcasts, film and television. People are interested in what happened, who did it and why. Archaeology of murder, however, goes deeper than that and examines the social and political context in which the murder was committed, the actions and behaviours of the police, the victimology of those involved and how society responded to the often alarming circumstances as they became more widely known. It is a method by which we can begin to better understand society and not simply accept the facts at face value. I focus primarily on early to mid-twentieth-century crimes and emphasise the social and political constraints in which the police operated. It is a powerful tool in helping to understand and explain police behaviours and how society responded, and gives us a greater understanding of how and why the police operate in the manner they do today.

Let us take an example. On 1 May 1924, police were alerted to a bag containing bloodstained garments which had been found in a left luggage compartment at Waterloo railway station. It was thought that the clothes could be connected to an illegal abortion, and observations were carried out on the locker. The following day, Patrick Mahon recovered the bag. He was immediately approached by a police officer who said, “You will have to come with me to Kennington Road police station”. Mahon replied, “Rubbish”. The officer said, “No, it is not, and you will have to do what I say”. Mahon was then, to use the exact words of the arresting officer, ‘detained’ at the police station. Mahon was then ‘detained’ at a series of police stations where he was repeatedly questioned but remained silent until ultimately he said, “I might as well tell you the truth.” He then made a series of written statements in which he admitted he had murdered a woman with whom he had been having an affair, dismembered her body and threw the body parts through a train window.

At the time, police procedure was governed by the Judges’ Rules, which had been implemented informally in 1918 and which were intended to put some measure of control around the handling of people suspected of committing crime. The rules were, to say the least, confusing and contradictory. Neither the courts nor parliament saw the necessity of introducing legislation which would have given clearer instructions. The consequence of this was that the police were able, or perhaps even forced, to interpret the rules as they saw fit. However, even the most liberal interpretation of the rules meant that if a person is suspected of a crime, he must be arrested and cautioned (told that he need not say anything at all).

If we now return to the arrest of Patrick Mahon in 1924, he was neither arrested nor cautioned up until the point he had been detained for several days and then decided to make his confession. The police argued that since Mahon had merely been detained, and not therefore been arrested, there was no need to administer a caution. This, I would argue, was a breach of the Judges’ Rules. However, the police interviews in this case were later described as being of ‘conspicuous skill, tact and ability in obtaining from [him] what amounted to a confession of a murder that everyone was ignorant of except Mahon himself’. In other words, the practice of holding a suspected murderer in custody with no warning of his rights was regarded by the courts and the newspapers as acceptable practice, despite the advice laid down within the Judges’ Rules. Why was this?

Well, put quite simply, the public was concerned that there was a growing tendency for parliament and the courts to put too many obstacles in the way of the police being able to investigate murder effectively. Placing these constraints on police officers was leading to an increase in unsolved murders, and they should not have to investigate serious crime with one hand tied behind their backs. The Mahon case was typical of the period and an example of the police operating within a social and political environment which had little appetite for change.

Fast forward to 1984, and Parliament now introduced the Police and Criminal Evidence Act, designed to better control police practice in the investigation of crime following decades of concerns about miscarriages of justice and unacceptable police behaviours. Viewing this through the prism of today’s standards and expectations, the Act has markedly reduced these concerns and brought about a legal framework within which the rules are much clearer, if not wholly unequivocal. The courts and the public alike are reassured that the matter is now much better under control. But my attention was taken by another high-profile case, which hit the newspapers from 2011 onwards; the murders of Sian O’Callaghan and Becky Godden-Edwards. The suspected murderer in these cases was a man called Christopher Halliwell, and the investigation would even result in the TV series, A Confession. It is remarkable that the arguments of the 1920s would be so relevant a hundred years later, and the case serves as an example of how society views and understands police practice in modern times.

The case is, legally, a very complex set of circumstances, and so a quick summary is necessary. Sian was reported missing in 2011, and it quickly became apparent that she had either been abducted (and was still alive) or that she had been murdered. Either way, no body had yet been found. Through particularly good police work, the suspect Halliwell came to the attention of the police, but there was insufficient evidence to make an arrest. Police focused on gathering further material, which may later prove useful in any criminal trial. However, events overtook them and their hand was forced, resulting in his arrest for the suspected kidnapping of Sian. It became clear very quickly that Halliwell had no intention of making any confession.

The investigating officer decided to breach the rules laid down in the Police and Criminal Evidence Act 1984 (PACE) and questioned Halliwell in an isolated field, aware that the prisoner ought to have been taken to the nearest police station. He decided to question Halliwell under a provision of PACE, which allowed for ‘urgent interviews’ in specific circumstances. It was a loose interpretation of the rules, and he was aware that his actions were likely to attract criticism. As a direct consequence of this, Halliwell admitted the murder of Sian O’Callaghan and took the officer to where the body had been concealed. He then admitted to the murder of Becky Godden-Edwards four years earlier and again took the police to the spot where he had buried the body. It can be seen that, despite the illegal activity of the investigating officer, the two bodies would never have been recovered otherwise, and it most likely would never have been known that Godden-Edwards was even dead and that Halliwell had killed her.

There was other independent evidence against Halliwell in the case of Sian’s murder and he pleaded guilty. However, the case against Halliwell in respect of Godden-Edwards was dismissed as his confession was obtained as a result of breaches of PACE. The investigating officer was disciplined and resigned from his Force. The mother of the victim was wholly supportive of the officer’s actions since, without him, her daughter’s body would never have been found. Indeed, many people supported the officer’s action since the means justified the end. In other words, it may be that the police broke the rules, but it doesn’t really matter as a greater good came of it. This position was reinforced when Halliwell was later tried for the second offence and was again convicted.

I have given many hundreds of talks to a range of audiences, and it is a common theme that people feel that the police in the Halliwell case should never have been criticised. This poses an important point. It seems that where the police appeared to have acted morally, society feels that this overrides any requirement to comply with the law. This was exactly what happened in 1924 when Mahon was arrested. When society feels that the right person has been arrested, the small issue of legislative compliance goes out of the window.

Rules and regulations are brought into being by parliament, often as a result of social and political pressure. Both the Judges’ Rules in 1918 and the Police and Criminal Evidence Act in 19184 were brought into being due to overriding concerns about police malpractice. Yet, it seems, there remain occasions when the public is content to let the police simply get on with their job without unnecessary interference. This is the point: to understand the details of any case, now or in the past, you need to understand the social and political environment in which the actors operated. That is archaeology of murder.