The first thing to remember is to take seriously the words of the Miranda warning,
"You have the right to remain silent. You have a right to a lawyer. ... Anything you say can and will be used against you."
US precedental case law (Supreme Court cases) talk about a point when a police inquiry changes from "investigative" to "accusatory". This has legal meaning regarding such things as Miranda rights, but you should consider all questioning accusatory unless you have reason to believe otherwise. The controlling issue is whether the police are trying obtain information about you. If they are, it's time to keep your mouth shut.
There are certain situations where this cannot be done. If you are stopped for a traffic violation, you will typically be asked a question which has an incriminating answer. But even there, it is possible to politely decline. "I try to observe traffic laws and drive safely." (On the other hand, if you intend to pay the ticket without going to court, then it's okay to confess.)
Whatever you do, decide ahead of time.
Determine in advance if it would be beneficial to attempt to give explanations of a medical condition or disability. In many cases, it is not.
If a previous incident will be on the computer records, advise the
police of it. Sometimes this will be irrelevant, as with a traffic
stop. There are even times when this can turn out to be very
useful to you, for example if you are reporting harassment from
someone who has previously invoked the criminal process.
First, as far as incriminating evidence is concerned there is no meaningful difference. Consider the interrogation to begin with the word, "Hello.". If you are at a traffic stop, don't expect a cinematic spotlight or actual Gestapo agents asking questions. The interrogation begins "here and now".
In the US, the only relevant difference between investigation and interrogation is that, in the investigative stage, the police do not need to actually recite the Miranda rights. The Supreme Court describes the process progressive from "investigative" to "accusitory", but a valid confession is evidence, regardless of the stage of the process.
(Note that a formal questioning procedure is typically not used in the US.)
Many people confuse the nature of the interrogation with that of questioning, and confuse what should mentioned in the interrogation with that of the investigation.
Once in the interrogation process, the police purpose is no longer investigative. Police interrogators are expert at asking questions that:
Some interrogators may try to confuse the suspect, distort the suspect's reasoning, and tangle the suspect's thoughts by throwing many questions at the suspect at the same time and not allow the suspect a chance to answer. This is combined with coercion, thereby intimidating the suspect to speak quickly or provide a confession. The confession can easily be false, but still used against the suspect.
Remember that your refusal to talk does not suggest guilt.
If you start to describe or defend the incident, no matter how insignificant you think the information is, you may be opening a door which cannot be closed until you incriminate yourself.
One classic interrogation technique is the "good cop, bad cop" technique. One interrogator acts roughly and is unsympathetic. The other interrogator offers a more sympathetic attitude, which includes kind treatment, expressions of understanding and benevolence. The "good cop" may "cry crocodile tears" (show false sympathy) or offer fatherly advise, in order to urge you to confess.
If you are imprisoned, do not discuss the incident with cellmates prior to trial.
first posted 10 Nov 02; rev 3-May-2018 This page copyright
2002, Stan Protigal