Regarding U.S.A. Police or other officials of ‘authority’.
Not everything that agents of the FBI, the Department of Homeland Security, or local law enforcement decide to tell you is actually true. Not everything that they suggest that you do is actually a good idea.
Before you interact with any agents of the government, it is essential that you know your rights.
The ACLU Nationwide has a fantastic, regularly updated “Know Your Rights” page with downloads here:http://www.aclu.org/drug-law-reform-immigrants-rights-racial-justice/know-your-rights-what-do-if-you