They knew the answers to their questions before they asked them because they were monitoring his phone, so why ask if you're not looking for a slip up or, as they put it, a lie. That's trickery, or as they say in legal terms, entrapment.
so the requirement to make a plea in court is "entrapment" to you?
You've got the cart before the horse there, bud.
What is the cart and what is the horse? That expression means, "you're doing it backwards". Are you trying to say that first comes the plea and then comes the charge? Or, first comes the charge and then comes the investigation? You make no sense. Your idea of how the law works sounds like something out of a cartoon. "I'm sorry Mr. Mayor, but the Joker has to go free. We already know he robbed the bank because of the hidden video, so we can't ask him about it. since he won't get a fair trial without the opportunity to address the evidence, as required by law, we will have to let him go".
The whole idea that one can even consider that asking a question about a person's activities is entrapment because they may want to cover up something they have done, but is not entrapment if you didn't already know the correct answer to the question, is ludicrous.
Such a target of an investigation is free to exercise their 5th amendment rights.
Speaking of the 5th... What, in your imagination, is the purpose of the 5th Ammendment to the US Constitution? Does it have a use and if so, what is that use and how does it apply to a citizen being questioned by an investigative entity? Now how does that jibe with your idea that questions can possibly be any kind of entrapment, in any situation at all?
You keep using that word incorrectly.. entrapment. As explained to you already, entrapment requires an elaborate scheme to trick a law abiding person into committing a crime that you specifically setup to catch them doing.... someone used the perfect example of leaving a bag of money in the street and then arresting the first random person that walks by that touches it for theft. There is no great mystery.
I think the word you are searching for to accurately describe your objection is "incrimination". Not "entrapment". Asking someone if they murdered the postman is not entrapment, it is baiting them to incriminate themselves. NOW go look up the 5th Amendment.
It is easy to see why a Trumpette would not want to use the correct word... incriminate. Certainly you would be concerned about a criminal you want to be left alone incriminating themselves by standing trial (or being interviewed in a pre-trial meeting) where their attempts to cover up their crimes would itself be a crime.