I feel sorry for the officer that tazes my pregnant wife and causes my wife to spontaneously abort because he insisted on having an incriminating instrument signed, despite the fact traffic camera tickets are not signed
Hopefully, your wife follows the laws and gets out of her car when a policeman asks her to. If she does, no problem and no tazer, only a speeding ticket. End of story.
Hopefully, your wife would be literate enough to read the document and determine that it is NOT incriminating, merely an agreement to appear in court. See, Court is where you argue these things, not the side of the road. If you and your wife don't understand that then you might well have something bad happen to either you or your wife.
incriminating instrument signed, despite the fact traffic camera tickets are not signed
Then work to get the law changed. Until then, we go by laws on the books.