You don't have to attack third party doctrine to get a sensible result in light of modern technology. A straightforward wrinkle to add to Smith is that unlike the plain text call information in Smith, an encrypted Skype call or encrypted cloud storage account is something people can have a reasonable expectation of privacy in.
The only reason you have to attack a Smith head-on is to validate the current monetization structure of the Internet. Encrypted data isn't very lucrative, after all. I don't think that's a valid justification for interpreting the Constitution one particular way.
> A straightforward wrinkle to add to Smith is that unlike the plain text call information in Smith, an encrypted Skype call or encrypted cloud storage account is something people can have a reasonable expectation of privacy in.
You're just hitting the heart of why Smith is broken. The content of a traditional phone call isn't encrypted but Smith still doesn't allow the government to record it without a warrant just because the call is transmitted via third party equipment, am I right? The issue is the metadata. But encrypting the call doesn't hide the metadata which is still needed in order to route the call.
Verizon Wireless knows where you are 24 hours a day, Facebook knows who all of your friends are and when and how often you communicate with each of them and Amazon knows everything you buy and what books you read. Encrypting the content of messages changes none of that. You're already paying money to Verizon and Amazon rather than viewing ads, it doesn't stop them from storing the metadata.
The only reason you have to attack a Smith head-on is to validate the current monetization structure of the Internet. Encrypted data isn't very lucrative, after all. I don't think that's a valid justification for interpreting the Constitution one particular way.