Abstract: Systems and methods for email processing are described. Embodiments of the present disclosure identify a plurality of email recipients, wherein each of the plurality of email recipients has an email address associated with one of a plurality of internet service providers (ISPs); identify a plurality of internet protocol (IP) addresses, wherein each of the plurality of IP addresses is available for sending email from a user to the plurality of email recipients; compute an ISP-IP score for each of a plurality of ISP-IP pairs based on email delivery statistics; select an IP address from the plurality of IP addresses corresponding to each of the plurality of email recipients based on the ISP-IP score; and transmit an email to each of the plurality of email recipients from the selected IP address.

Abstract: Secure auditability of monitoring processing using public ledgers that are particularly useful for monitoring surveillance orders, whereby an overseeing enforcer (“E”) checks if law enforcement agencies and companies are respectively over-requesting or over-sharing user data beyond what is permitted by the surveillance order, in a privacy-preserving way, such that E does not know the real identities of the users being surveilled, nor does E get to read the users' unencrypted data. Embodiments of the present invention also have inbuilt checks and balances to require unsealing of surveillance orders at the appropriate times, thus enabling accounting of the surveillance operation to verify that lawful procedures were followed, protecting users from government overreach, and helping law enforcement agencies and companies demonstrate that they followed the rule of law.