Suppose you are just walking along the street and a cop approaches you. You haven't done anything or seen anything, but the cop has. He's just not willing to tell you, as he doesn't want to prejudice the case he's building against a perp you passed on the sidewalk a minute or two earlier.
So the cop asks your name, address and DOB. You say, "Why? Are you going to arrest me for being on the city street?"
"Only if you refuse to give me your name, address and date of birth. I believe you may know something about a crime."
"What!? What happened? Tell me."
"Can't tell you that. I just need your name, address and date of birth. Now, are you gonna give it to me or am I gonna hafta run you in?"
So whatcha gonna do? Punt?
Tell him your name is George Mason, and your address is 10709 Gunston Road, Mason Neck, Virginia, 22079. Tell `em your serial number is A-7713. If enough people do this, maybe they'll get the point.