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Thanks for your replies, but at this point I am convinced we are having two different conversations. I will try to pick up this idea with you at a later time because I am curious about your perspective considering your expertise.
To try and plant some seeds hoping our next conversation will be more productive--
The "third parties" are communications providers. The communications providers are also being searched.
Let's say I am accused of stealing a refrigerator and the police believe that you are not involved, but the cassette tape in your answering machine may hold indirect evidence of this theft.
You are the "communications provider" in this metaphor. Your house is being searched for evidence against me but, you still have fourth amendment rights.
Read my original post with this metaphor in mind and I think we will come closer in understanding.