Electronic voting machine have the issue of being potentially hacked (Plus closed source is weird). So in many places a paper trail is produced in parallel to electronic tallying.
However some object to having a paper trail due to tree consumption.
If we cannot trust voting machine then what could be done to create an audit-able trail is to create a physical electrical bus standard. An CAN bus for election. :D
Essentially you have a single master input device that accepts a data card containing your vote settings. To which the master device will emit the vote setting on the data bus.
Attached to the data bus is the master recorder of votes. But in addition, there are also secondary recorders and auditing circuits that provides monitoring of the data stream, as well as displaying to the voter what it sees.
What this ensures is that if you have multiple different manufactures supplying various master recorder and auditing and display screens. Then you will have to corrupt every single one of them to get away with fraud.
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This also allows for inserting "test votes" module which appears to be normal votes with normal IDs, but after voting... you can read the 'test module' and check that the vote has not been tampered with in the results.-- mofosyne, Nov 23 2014 We use CAN bus in autos. Security against hacking is not an insignificant problem we face as a result.-- RayfordSteele, Nov 23 2014 Can the CAN bus be used on vehicle buses to give riders political sway on current issues? One vote per trip but you can vote as much as you like.-- wjt, Nov 24 2014 random, halfbakery