Police caution

The Police caution is presented as a procedural warning about a suspect’s choice to speak and the possible evidential use of what is said. Its clearest instance comes at the start of Jonathan Devlin’s interview, where the detectives state that he is not obliged to answer, but that anything he does say will be written down and may be used in evidence. The scene also makes clear that receiving the caution does not, by itself, mean that he has been arrested.

Wording and Function

Before questioning Jonathan Devlin, Cassie Maddox gives the caution in the interview room. Its terms establish two points: he may choose whether to speak, and his words may become part of the evidential record. The warning frames the interview as a formal police procedure, rather than an informal conversation, while leaving the decision to answer with Jonathan.

Use in Jonathan Devlin’s Interview

Jonathan immediately asks whether he is under arrest and what he is suspected of. Rob Ryan explains that the caution is routine and says that the detectives want to update him on the investigation and see whether he can help move it forward. Cassie Maddox likewise tells him that, if he were under arrest, he would know. The exchange distinguishes the warning about speaking from the separate question of his arrest status; the detectives then invite him to sit and proceed with the interview.

Procedural Boundaries

The caution concerns Jonathan’s own answers and their possible use as evidence. It is distinct from the evidentiary issue raised elsewhere when Rosalind Devlin begins to recount what Jessica Devlin told her: Rob Ryan says he needs to hear the account from Jessica herself because Rosalind’s version would be hearsay and inadmissible in court. The two moments concern different procedural questions—what a suspect is told before answering, and whether a witness’s account is admissible—and the narrative does not treat them as interchangeable.

Contrast with Confession-Seeking

The interview with Damien Donnelly later shows detectives using a different kind of questioning: Cassie Maddox advances her theory that the killer was not inherently violent, while Ryan and Maddox describe the psychological cost of concealing a crime and press Damien to respond. Damien eventually nods when Ryan asks whether their account sounds familiar, then gives an account of Katy’s killing. The cited passages do not state whether a caution was given to Damien, so they do not establish a procedural comparison between the two interviews. They do, however, distinguish the caution’s stated terms from the persuasive and confrontational methods used to elicit a confession.