Texting at stop light.. Stranger took a picture.! Domestic Violence & Civil Orders

I don't see anything in your scenario which would lead to anyone being prosecuted for child endangerment.

If you are moving about in public view, anyone can take a picture of you.
Heck, the state does it everyday all across this country, as do businesses, government entities, and simple homeowners using those pervasive security cameras.

 

The activity you describe is ONLY illegal if one is first charged with it, and subsequently convicted.
Otherwise, if the police don't issue you a citation, it never, ever happened!

 

Although some busy body could take such a picture, show it to one of your state's Blue Knights, so what?

There are many problems with someone attempting to snitch out what they believe is "texting".

Peace officers in Nevada are not authorized to arrest anyone for a misdemeanor offense without a warrant, unless the offense was committed in the officer's presence.
What you describe is a misdemeanor at best, a traffic offense at least.
There are a few exceptions to the police power to arrest in Nevada, such as a mandatory arrest for domestic battery occurring outside of the officer's presence, which upon investigation permits the officer to arrest the offender upon his or her reasonable suspicion or belief.

Nevada Revised Statue (NRS) 171.126 authorizes, "a private person may arrest another person for a public offense committed or attempted in the presence of a private person."

In Nevada, and in many other states, a citizen's arrests is rare, because the citizen must also convince the responding officer(s) that an offense occurred prior to the arrival of the police. Plus, the private citizen arresting the other person incurs the burden of summoning witnesses, appearing in court, and testifying against the offender — such tasks are normally performed by sworn law enforcement officers.

Finally, the police have many more important duties to carry out than to allow busy bodies and grudge holders to start arresting people for traffic offenses.
In your hypothetical, any first year law student could successfully defend any accused driver, effectively nullifying these silly arrests.

Thanks for taking me back to my law school days, interesting "hypo".