Texting while driving is illegal in Washington however this dangerous activity still takes place.

RCW 46.61.668
Sending, reading, or writing a text message while driving. 

 (1) Except as provided in subsection (2) of this section, a person operating a moving motor vehicle who, by means of an electronic wireless communications device, sends, reads, or writes a text message, is guilty of a traffic infraction.... (full law).

This 15 minute video called 10-85 Echo is a reminder that texting while driving is deadly.