DO NOT call the police until you first talk to an attorney licensed to practice in your jurisdiction!! You need to know what your risks are, along with your obligations!
If you call the PD, you may be placing yourself at their mercy--and what if they have none?
That's the truth. Police are some of the most ignorant people you'll ever meet in regards to proper application of the law. I wouldn't trust any of them with such information without representation.
That and the fact that police aren't empowered nor are they in any way authorized to render a binding legal determination. (Elementary school civics: three branches of government -- legislative, judicial, and executive. Police agencies are part of the executive branch, not the judicial as some would accept.)