intent can be unclear. Like electronic ballot markers, DRE's can be programmed to offer ballots in multiple languages, and they let people with disabilities vote without assistance, which would remove the anonymity of their vote. The machines can use headphones and other adaptive technology to provide accessibility. Additionally, with DRE voting systems there is no risk of exhausting the supply of paper ballots, and they remove the need for printing paper ballots, which cost $0.10 to $0.55 per ballot, though some versions print results on thermal paper, which has ongoing costs. Issues Skepticism about the integrity of DRE voting machines led to the creation of election forensics, which can help identify election fraud. Delays in voting DRE's can cause more delay than paper ballots at busy times, since every voter needs access to a machine. Queuing theory calculates that waits of an hour result from known variations in when voters arrive, number of voters per machine, and average time a voter spends with a machine. Errors Issues have included public web access to the software, before it is loaded into machines for each election, and programming errors which increment different candidates than voters select. 2009 German court ruling In 2009, the Federal Constitutional Court of Germany found that with voting machines the "determination of the result must be able to be examined by the citizen reliably and without any specialist knowledge of the subject." They further found the DRE-type voting machines, used in parliamentary elections under current German law, permitted voting machines but were unconstitutional without further qualification. The decision does not ban electronic voting but implements a higher standard. Demonstrated laboratory attacks Diebold Election Systems AccuVote-TS (Manipulation of the votes by the Princeton University) Nedap ES3B (Manipulation of the votes by a citizen group) SDU voting computers (Violating the secrecy of the ballot using Van Eck phreaking, tested by the Dutch secret service AIVD) Attacks have also been performed on both DRE machines and optical scan voting machines, which count paper ballots. (See California study, "Security Analysis of the Diebold AccuBasic Interpreter"). Whether it is a DRE or an optical scan machine, the opportunity for tampering applies to persons with inside access (including government workers) and to a lesser extent, outside hackers. Therefore, framing election tampering issues as "hacking" may not be an accurate framework for public concerns. Within the context of protecting voting rights, it would not matter