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12 Sep 2016

Making a Murderer; the admissibility of Brendan Dassey’s confession in UK law


On 12 August 2016, the US District Court of the Eastern District of Wisconsin gave its decision in the case of Brendan Dassey v Michael A Dittmann. For fans of the Emmy-nominated Netflix hit Making a Murderer, this decision has been long-awaited.  Dassey is the nephew of Stephen Avery, both of whom were convicted in relation to the rape, murder and mutilation of Teresa Halbach on 31 October 2005.

The bulk of the prosecution’s case against Dassey was confession evidence, predominantly given in police interview on 1 March 2006. The recent challenge by Dassey was a petition for a writ of habeas corpus; a claim that he was being unlawfully detained. This was brought against the warden of the detention facility at which Dassey was being detained.

Dassey made two claims for relief; firstly in respect of the “indefensible” misconduct of his defence lawyer, Len Kachinsky, and secondly in respect of his confession evidence. The court found that it was not permitted to decide the claim relating to Dassey’s lawyer’s conduct, as the basis of the argument was different to that which was previously argued before the Supreme Court. In respect of the confession, Dassey claimed that it was obtained in violation of the Fifth Amendment. Dassey did not deny having made the confession; his claim was that he had made it involuntarily. It is on this claim that Dassey succeeded, and his writ for habeas corpus was granted.

The court determined that Dassey’s confession had been rendered involuntary based on a number of factors:

i)   The investigators repeatedly, and falsely, claimed already to know what had happened on the day of the murder, and incorrectly assured Dassey that he had nothing to worry about.

ii)  Dassey was just 16 at the time of his confession, and was interviewed without either a lawyer or an appropriate adult present.

iii) Dassey was of low IQ and had learning difficulties, making him particularly susceptible to leading questions.

The court was not required to consider whether the confession was reliable, only whether it was voluntary.

This article considers whether Dassey’s confession, had it been before a UK trial court, would have been admissible under UK law. It starts by outlining the key features of the confession, before examining the applicable UK law on confessions and exclusion of evidence, before applying this legal framework to Dassey’s confession and asking whether, and how, the confession would have been excluded under UK law.


The court identified seven key features of Dassey’s confession in reaching its decision; all of these would also be considered as relevant by a UK court.

  1. Dassey was just 16 years old at the time of his confession. He had an IQ of around 74 and received special educational support services, making him more susceptible to coercive pressures than a peer of higher intellect. Dassey was interviewed without the benefit of a lawyer, parent or other appropriate adult looking out for his interests.
  2. The interview occurred during civilised day-time hours and was not particularly prolonged. Dassey was left alone for less than two hours (50 minutes being the longest single stretch) and was offered food and beverages. Dassey was interviewed at a police station but in a “soft interview room”, with carpet and upholstered furniture.
  3. Dassey was advised of his rights under Miranda; the right to silence, the right to stop the interview and the right to have a lawyer appointed for him and present during interview; he declined to have a lawyer present and chose to answer all questions. He had had no contact with the police prior to the Halbach investigation and so had no prior experience in the criminal justice system.
  4. The investigators did not use aggressive or confrontational tactics. They did however exploit the fact that Dassey had no appropriate adult present by repeatedly suggesting that they were looking out for his interests: “…we’re on your side…”, “I’m your friend right now but I … gotta believe in you and if I don’t believe in you, I can’t go to bat for you” and “… yeah we’re cops … but I’m not right now. I’m a father that has a kid your age too. I wanna be here for you. There’s nothing I’d like more than to come over and give you a hug cuz I know you’re hurtin’.” Officer Wiegert repeatedly touched Dassey’s knee in a compassionate and encouraging manner.
  5. The investigators made repeated statements to the effect of a) “we already know what happened”, and b) “you don’t have anything to worry about”. The investigators told Dassey more than 25 times during the interview that they already knew what happened: “… we know, but we need it in your words … I can’t say it”, “…we need to hear it from you, it’s Ok. It’s not your fault”, “let’s get it all out today and this will all be over with”, “you were there when she died and we know that. Don’t start lying now”, “we know you shot her too”, “it’s not your fault.” The Respondent acknowledged that the most damaging admissions were all made as the investigators encouraged Dassey to tell the truth because they “already knew” what had happened. Officer Wiegert also told Dassey that “honesty is the only thing that will set you free”; whilst the court acknowledged that was just an idiom, testing revealed that such idioms were an aspect of abstract language that Dassey had difficulty understanding.
  6. Dassey failed to grasp the seriousness of the situation and the confession he was giving. He exhibited no signs of agitation or distress throughout the interview; he sobbed only after being told he was under arrest, after confessing. Even after his confession he twice expressed his expectation that he would return to school that day. When told he was under arrest he asked whether it was “only for one day”.
  7. The investigators’ actions amounted to deceptive interrogation tactics. More than merely assuring Dassey that he would not be punished if he admitting participating in the offences, the investigators suggested to Dassey that he would be punished if he did not tell “the truth”. Because the investigators’ assertions that they already knew what had happened were often false, “the truth” meant whichever of Dassey’s versions of events they eventually accepted. This led him to believe that as long as they accepted his story, he had no need to fear negative consequences.

No ill motive was ascribed to the investigators by the court; rather than an intentional effort to trick Dassey into confessing, they were held to have probably failed to appreciate the effect that their statements had on him.


In UK law, a confession is any statement “wholly or partly adverse to the person who made it, whether made to a person in authority or not and whether made in words or otherwise” (s82(1) of the Police and Criminal Evidence Act (“PACE”)). By virtue of s76(1) of PACE 1984, a pre-trial confession will be admissible at trial to prove the truth of its contents (ie to prove the defendant’s guilt).

Different tests are applied in the UK courts than in the US courts; there is no right to challenge a confession in the UK on the basis that it was involuntary. Rather, the confession can be ruled as inadmissible under UK law if any of the following three tests is satisfied:

  1.  the confession was obtained by oppression (under s76(2)(a) PACE),
  2.  The confession was made in consequence of anything said or done which was likely, in the circumstances existing at the time, to render unreliable any confession which might be made in consequence thereof (under s76(2)(b) PACE), or
  3.  the admissibility of the confession would render the proceedings unfair (under s78 PACE).

These will now each be considered further.

Challenging the admissibility of a confession under s76 of PACE 1984

The admissibility of a confession can be successfully challenged under s76(2) if the confession was or may have been obtained –

a) By oppression of the person who made it (s76(2)(a)), or

b) In consequence of anything said or done which was likely, in the circumstances existing at the time, to render unreliable any confession which might be made in consequence thereof (s76(2)(b)).

Where either of the above factors can be shown, the court must not allow the confession to be used as evidence by the prosecution, unless the prosecution prove beyond a reasonable doubt that the confession was not so obtained. The truth or otherwise of the confession is not relevant; the issue is whether the confession was obtained by oppression or in circumstances which render it unreliable.

Oppression, for the purposes of s76(2)(a), is defined in s76(8) as including “torture, inhuman or degrading treatment, and the use or threat of violence…” In R v Fulling [1987] 2 WLR 923, the Court of Appeal included within the definition “the exercise of authority or power in a burdensome, harsh or wrongful manner; unjust or cruel treatment of subjects, inferiors etc; the imposition of unreasonable or unjust burdens”.

For a confession to be successfully challenged under s76(2)(b), something must have been said or done, usually by the police, which might have caused the defendant to make a confession for reasons other than the fact that he had actually committed the offence and wanted to admit his guilt. No breach of PACE Code of Practice C is required, however it will frequently be a breach of Code C which will be the subject of such a challenge. Examples of the types of breach which may lead to an exclusion on grounds of unreliability include: denying a suspect refreshments or rest periods; offering a suspect an inducement to confess; misrepresenting the strength of the prosecution case; questioning a suspect in an inappropriate way, or at all if the suspect was not in a fit state to be interviewed; and threatening a suspect.

A Code C breach alone is insufficient for the confession to be excluded; there must be a causal link between the breach and the unreliability of the confession subsequently made.

Challenging the admissibility of a confession under s78 of PACE 1984

S78 provides the court with a general discretion to exclude prosecution evidence, including confession evidence. A confession may be excluded under this section if the court considers that the admission of the confession would have such an adverse effect on the fairness of proceedings that it ought not to be admitted.

Where, as in Dassey’s case, the defendant accepts having made the confession, the court is likely to exclude the evidence if there are breaches of PACE 1984 and/or the Codes of Practice in obtaining the confession and the breaches are both significant and substantial. Such an example would be a failure to caution an individual who is unfamiliar with the practice and procedure of being interviewed as a suspect under caution, and so unaware of the right to silence and the privilege against self-incrimination. However, wrongdoing on the part of the police is not always necessary for s78 to apply.


The US and UK courts apply different tests; Dassey succeeded in showing that his confession was involuntary, which, as explained below, finds a parallel with the test of “oppression” under s76(2)(a) PACE. However, had Dassey been challenging his conviction in a UK court, he could have relied not just on oppression under s76(2)(a) PACE, but also on the separate tests under s76(2)(b) and s78 PACE.

Each of the three tests is now considered in turn, alongside the facts of Dassey’s case.

1. S76(2)(a) PACE – the “oppression” argument

At first glance, the oppression argument under s76(2)(a) PACE could be easily dismissed as it requires some obvious mistreatment of the suspect which was missing in Dassey’s case. 11.5 of Code C states that “No interviewer may try to obtain answers or elicit a statement by the use of oppression”. In Fulling, the court found it hard to envisage any circumstances in which such oppression would not entail some impropriety on the part of the interrogator. In Dassey’s case, the US court found no ill motive on the part of the interviewing officers. However, the case of R v Mushtaq [2005] 2 Cr.App.R. 32, HL provided a wider definition of the type of conduct which could be considered oppressive: “…questioning which by its nature, duration or other circumstances (including the fact of custody) excites hopes (such as the hope of release) or fears, or so affects the mind of the subject that his will crumbles and he speaks when otherwise he would have stayed silent.” This wider definition is analogous to the US requirement that the confession is “involuntary”; the suspect is oppressed and so confesses against his will. The questioning style employed by Dassey’s interrogators could easily be seen to have excited hope in Dassey, that if he simply told the officers what they wanted to hear, he would be protected from punishment. This hope will have been enhanced by the officers’ paternalistic manner with him. For this reason, it is highly arguable that, in a UK court, Dassey’s confession would be excluded under s76(2)(a) as having been obtained by oppression.

2. S76(2)(b) PACE – the “unreliable” argument

The second challenge to admissibility, that the confession is rendered unreliable due to something said or done at the time of the confession under s76(2)(b), is arguably a clearer basis for a ruling of inadmissibility. The seven features of the confession listed above, when analysed cumulatively, could well be said to render Dassey’s confession unreliable. In particular, the failure to ensure that an appropriate adult attended the interview would have constituted a clear breach of Code C. Under UK law, not only would an appropriate adult have been required due to Dassey’s age, but “mentally vulnerable” suspects also require an appropriate adult to be present. Paragraph 11C of the Code C Notes for Guidance highlights that “Although juveniles or people who are…otherwise mentally vulnerable are often capable of providing reliable evidence, they may, without knowing or wishing to do so, be particularly prone in certain circumstances to provide information that may be unreliable, misleading or self-incriminating. Special care should always be taken when questioning such a person…” The US judgment noted that there is no requirement in US law for an appropriate adult to be present in interview. Rather than the officers taking special care with Dassey though, his vulnerabilities were instead exploited.

Of even greater importance than the absence of the available adult was the questioning technique adopted by the officers. Paragraph 11.15 of Code C states that “…no interviewer shall indicate, except to answer a direct question, what action will be taken by the police if the person being questioned answers questions, makes a statement or refuses to do either.” Whilst the officers at no point made any explicit false promises of leniency, the US court found that their actions “amounted to deceptive interrogation tactics” and there was a suggestion that he would be punished if he did not tell them what they wanted to hear. As a result, Dassey’s evidence was inconsistent throughout. He relied on the confirmation and praise of the officers in settling upon the facts of his final confession. When Dassey’s particular vulnerability is considered alongside the questioning techniques used by the officers, it is difficult to see how the unreliability test in s76(2)(b) PACE would not be satisfied.

3. S78 PACE – the “unfair” argument

The final challenge to the admissibility of Dassey’s confession is the discretionary power to exclude evidence under s78 of PACE. As noted above, a breach of Code C may lead to the exclusion of a confession under s78 but not every breach will trigger exclusion, and evidence may be excluded where there has been no breach. Here there were clear breaches of Code C (see above). However, these breaches must be shown to have an adverse effect on the fairness of the proceedings.  There is no guidance on the application of s78 due to the infinite variety of circumstances which may exist, however, given the impropriety by which the confession was obtained, it is difficult to see how a Judge in the UK would not exercise the discretion under s78 PACE so as to exclude the confession.


There are three ways in which a confession, obtained in the UK, could be excluded under UK law. It would appear that, in Dassey’s case, all three would have applied. UK law is designed to protect those who are found confessing in precisely those circumstances in which Dassey found himself. The provisions of PACE and its Codes of Practice lend further protection, for example by requiring the presence of an appropriate adult in the interviews of juveniles, whereas US law does not.

Given that all three UK provisions would have likely resulted in the exclusion of Dassey’s confession, it is troubling that, in the US, Dassey was convicted almost solely on the basis of his confession evidence, and his conviction survived a number of appeals. This can be explained, at least in part, by Dassey’s incompetent pre-trial representation. But that is only part of the explanation, and it still took 10 years from being convicted to get to this point. One would hope that the UK legal system would have responded to such an injustice more swiftly.

This article was originally published in Criminal Law & Justice Weekly, and can be found here.

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