You spotted the weak link in this flowchart: &quot;Could YOUR answer (or silence) be used to make it look like YOU committed a CRIME&quot;. There is no way to know. When cop comes and  casually talks to you, he may not even consider you a suspect until later.<p>If you follow the watertight route, you may never talk to police:  <a href="https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=6wXkI4t7nuc" rel="nofollow">https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=6wXkI4t7nuc</a>  You must have constant adversary attitude towards police asking questions in every situation. 
In practice people never do that and usually nothing bad happens, but still... It&#x27;s part of the good police work to be casual and make people feel that people are  jerks if they don&#x27;t  cooperate.