"Black box voting" was coined by David Allen, a publisher, technical consultant and co-writer to author and activist Bev Harris.
Rhode Island Supreme Court Justice Horatio Rogers, in an 1897 dissenting opinion, wrote of one early mechanical voting machine that Rogers' criterion for whether a voting machine is a black box is strict: you must be able to sense that it works correctly as you use it.
A somewhat weaker criterion is sometimes accepted, based on whether the public is allowed to examine the mechanism, in a modern context, both the source code and hardware.
[4] Though source code may be available to voting system testing authorities and state or county election officials it can still be considered "black box" if it is not available to the public.
[6] Legislation has been introduced in the United States Congress to require public access to source code, hardware and firmware information, including the Voter Confidence and Increased Accessibility Act of 2007, introduced by Congressman Rush D. Holt, Jr.