The actions/conduct of the accused at time of arrest necessarily includes his relevant state of mind. As such, his conduct and actions, up to and including an omission or admission of guilt are admissible and generally always initially presented in Court by the Prosecuting Attorney or Crown.
It is almost impossible to "tell" the story in a courtroom of the investigation and arrest without uttering words about the accused's statement and reactions to arrest.
It is usually important to establish what the reaction to the evidence was when the defendant was questioned. It's revealing as determining relevant mindset and as we all know very telling when someone is confronted with evidence and their initial reaction.
This is true whether the reaction was because they are innocent or guilty.
I can't imagine the initial questioning and/or accused's statement wouldn't be included in court, whether he did or didn't do it.
Likely won't matter anyway. He and DP are probably doing the same thing as MS and his lawyer.....gaging the odds of a plea and selling the co-accused out vs. gambling on a jury returning a not guilty verdict.
I would think that an officer's testimony about their personal interpretation of a suspect's state of mind would hold less weight than a confession or denial. After all, that officer was not inside the suspect's head and not actually privy to what state their mind might have been in. And unless that officer is familiar with that particular person's normal reactions to certain situations as a control, how can they judge whether or not those reactions are normal for this suspect? For example, when a suspect in interrogation is told by police that they have something incriminating, and the suspect's state of mind appears to be disbelief and shock, how is the officer to know if the shock is because they are guilty and are shocked that such evidence was found, or if they are an innocent person shocked that there is evidence that may falsely convict them?
In this case one defendant was apparently arrested without incident and withstood 24 hours of intense interrogation without incriminating himself, how are the prosecutors going to use that to build their case for the jury? And how will that look for the defendant who had to be chased down by a tactical team?