‘verifiable paper ttrail’? no such thing in a computerized world.
paper ballots, hand counted by all sides.
I could design a device that had the advantages of both without much trouble. Allow the voter to use a touch-screen to register the vote, then print it out and have the voter confirm its veracity then drop it in a secured ballot box. When the voter is finished voting, record the vote locally AND to a remote site which would independently tally the result. Produces both an electronic and a paper record, which would greatly increase the barrier to forgery and fraud.
If the numbers don’t add up from all the different places where it is recorded, immediately secure all physical and electronic evidence and conduct a thorough probe of the actions of all individuals involved.
Increase sentencing to a felony with a minimum of 10 years with no parole for anyone convicted of willful alteration of the results of the vote.