In Germany, after §163 StPO and related the police may interview you as part of an investigation but if you are a suspect you must be told so prior to any interview. You are allowed not to make any statements, which is not considered any crime. Additionally, any statements you make may only be used for discovery of the truth but are not in of themselves considered actual proof or evidence in absence of anything else, word of mouth is not fully sufficient with a few minor exceptions outside the scope of the StPO.

The sentiment re. the police in germany is much different than in america, so my initial assertion does not at all equate to "what you say can't be used against you", rather "the police is in general trustworthy and non-malicious", which does not seem to hold true for america.

You should consider that not all countries think like americans and do not hold the same sentiment as americans. People in other countries think different, not the same.

In most countries the police does an independent investigation, and what you say to them can also be used in your defense.

The police can be called to testify on your behalf; just as well as they can testify against you.

Not always a reason to talk, but it makes it less dangerous to help the police. After all we do want to help the police catch criminals don't we?

Where are you not?

The right not to self-incriminate is pretty wide-spread :)