Here in Tx, refua\sal to sign the citation for a Class C Misdemeanor (Traffic Ticket and Minor Offenses) amounts to a demand to see a Magistrate Now.
Some departments will allow the "Refused to Sign" if the DA accepts. Not many do. The Supreme Court has Upheld taking minor violators before the Magistrate.
Naturally, some Lawyer out there will take a "Refused to Sign" on a citation and turn it into a case that the violator was denied his right to see the Magistrate immediately as prescribed in the law. Just as quickly they will scream Excessive Force and unlawful arrest if they are removed from the vehicle to see the Judge when they refuse to sign
I am unsure of the document you saw on the Randy Weaver story, but it could have been any number of administrative documents that go along with an arrest that are not citations
Regardless of the laws here I'm gonna sign, just can't win an argument like that on the spot with a cop and like the rest of the world, some can be a little, um, cranky.
Plus I suspect they must get a lot of grief. After getting a speeding ticket (deserved I might add) a while back after it was over the cop actually thanked me for being so polite so I figured he must not get a lot of that.
Didn't have any influence on me getting the ticket, but there are so many laws I suspect he could have started finding additional infractions if he had a mind to.