When police officers arrest a suspect and begin questioning, their goal is to get a confession. While any statements must be voluntary, the law allows police officers to use a variety of tactics to elicit them.
Many people assume that police officers will not lie during questioning. This is not the case. Moreover, if you make a statement because you believed a lie, under most circumstances courts will still consider your confession valid.
One common deception officers may practice is telling a suspect they already have physical evidence or eyewitness accounts tying the individual to the crime. They may tell you that they already know everything, so you should just confirm. Sometimes, they may ask you to confirm just a seemingly minor detail; ultimately, even this can lead to conviction.
Another frequent tactic is to threaten harsher legal consequences if you do not confess. An officer may tell you that you will face more serious charges. However, the police do not actually make this decision; it is the prosecutor who actually charges you and makes sentencing requests. Officers may also tell you that you are obstructing an investigation by refusing to talk. While obstruction is, in fact, a crime, merely refusing to talk is not obstruction of justice.
At times, police officers may assume a friendly demeanor and tell you they are on your side and just want to help you clear everything up. They may even tell you that you are not a suspect and they just want to ask you some questions. Believing these reassurances is a risk, however. Even if the police do not question you about a crime directly, their questions likely are designed to elicit the building blocks of the case against you -- your location at a certain time, your knowledge of events and other similar matters.
If you are arrested, it is in your best interests not to provide any statements and to have your lawyer present. A strong defense attorney can advise you as to the best course of action and create an effective strategy for your case.