Signing a traffic ticket can be an ominous feeling. It should not be. It is not as bad as you may think.
Purpose
The purpose of having the motorist sign the citation is not to get you to admit to guilt. It is merely you, the motorist, giving your word (by signing) that you will appear to address the citation in a court of law. Most (if not all) citations have something in the wording stating something like “by signing this citation you are not admitting guilt, it is only a promise to appear”. The citation is given in lieu of physical arrest.
The Citation
The citation is a pseudo legal document in which the officer is generating a summons for you to appear in court to face charges he has brought against you for a traffic infraction. By issuing the summons the officer is stating he is prepared to appear in court him/herself to bear witness as to what he observed you, the motorist, do which was illegal. It does not mean you are guilty of committing the infraction. The officer is just the witness on behalf of the jurisdiction that a traffic infraction was observed. In the United States you are still presumed innocent until proven guilty. The guilt it determined through evidence presented in court. The evidence presented in court is normally only testimony. If the prosecution has proven its case that the infraction has occurred then a judge will find the motorist guilty. If not then the judge finds in favor of the motorist and he is relieved of the charges.
In Lieu of Arrest
The citation is given in lieu of physical arrest. The jail does not want to be filled with people who have committed infractions. So instead of taking the motorist to jail the officer has the option of issuing the citation. Generally the citation means a promise to appear. If the officer can show that he reasonably believes that you will not show up for court as per the citation summons then he is justified in booking you in jail for the infraction. This is not common practice as it does not look too good for the department to arrest for a citation.
Do You Have To Sign?
Technically no you do not have to sign. However by you not signing the officer may have reason to believe that you would not show up for court and may arrest you to ensure you will be in court. You do not have to agree with the charges listed on the citation. You may think they are bogus charges. Instead of arguing with the officer on the street, take the matter to court where you can present your own evidence. The officer is not going to care what your evidence is. He will still fill out the citation if that is what he wants to do.
Will it do me any good not to sign the citation?
Generally no it will not do you any good. Whether or not you sign the citation you will be in court someday. If you drive off without signing the citation the officer may obtain a warrant for your arrest for charges related to the citation. With the warrant there are usually more financial charges incurred than the cost of the citation alone if you were found guilty. Charges such as vehicle impound if you are found driving a vehicle while having a warrant, higher bail amounts than the citation itself, and even bail bondsman charges should you use a bail bondsman. There will also be the fact you will have an arrest record now.
Is it worth it to go to court to fight a citation?
I like to answer yes to this question. What is the worst that can happen? The judge finds you guilty and you pay the full amount of the citation. If you go into the court prepared (not expecting) to be found guilty then it would not come as a surprise. If you are found guilty the judge has the option to lower the fine if he chooses. Who knows maybe you will be found not guilty and the citation goes away all together. There is also the chance the officer does not make it to court. In that event the prosecution has no witnesses and the judge must find you not guilty.
Conclusion
You should sign the citation. If you disagree with the citation take the matter to court and fight it out there. You can present your own evidence and you do not have to suffer the consequences of being jailed. Of course you can make your own decision, but in my opinion it is just not worth it in the long run.