So Siri is legal in California for texting while driving. The new law in California that allows hands free texting will not allow you to touch the phone or risk a ticket. 
Most have said that Siri does not pass the hands free test and will result in a ticket for using her. From all we can gather about the use of cell phone you can not touch it to be in compliance with the law. So, how does this work. Well if you use ear buds that have the controls build into the device it is quite easy. We can use the Apple ear buds to turn the music up, down and select the next song as this does not require you to touch the phone but push(click) the center of the microphone for the next song and pushing each end for the volume adjustment. So don’t touch that phone and just hold the center in just like you would the home button on the phone itself and presto! Ding, Ding … Miss Siri is waiting your command.
“Send message to my wife.(period)” (pause) Siri – “Ok, I can sed a text to Marilyn Hamilton for you … what would you like it to say?”
“Hi Honey,(comma) I am running a little late by about 30 minutes.(period) See you soon.(period)” (pause) Siri – “I updated you message, it says: ‘Hi Honey, I am running a little late by about 30 minutes. See you soon.’ Ready to send it?”
“Yes” Siri – “Okay I’ll send it.”
All of this with one push on the microphone piece of the ear buds and never touching the iphone. I believe this passes the test of the law. Now when my wife replies and my phone indicates new text message, with my new text tone, I again just hold the center of the microphone in and Ding, Ding … Siri is there and I ask.
“Read me my messages”(pause) Siri – “New message from Marilyn Hamilton it says. ‘Please pick up dinner as I am not in mood to cook.’ You can reply or read it again.”
“Reply”(pause) Siri – “What would you like to say?”
“See you soon and I will pick up Chinese. (period)” (pause) Siri – I updated your message it says, ‘See you soon and I will pick up Chinese.’ Ready to send it?”
Yes
So as you can see without touching the phone you can text all day but wait, to add frosting on the cake you can also use this method for emails. The only draw back is you can not edit the email so depending how well Siri understands your voice you may love this or hate it! There will be some mistakes that you will live with or not use it for this purpose. Also Siri will not read you your new emails but we can always hope for iOS-6 improvements.
Hope your found this useful and know that Siri is legal in California, just don’t touch that phone!
Bob