How about this?

"Thank you for your concern. I don't want to argue with you here on the street, and I will obey any clear order you give. However, as a knowledgeable cyclist I disagree with your interpretation of the law and proper cycling, and I wish to follow-up with you and your department at a time that is safe and convenient for you. May I please have your name and contact information?"

Certainly you could hand them a card with laws, references, your own identification info, etc. at this point. They may change their mind and leave you alone at this point, but if you get the contact information from them you can follow up in a setting that is less likely to get you tasered....