a mobility disability, such as hand limitations, verify a piece of paper alone, if that individual is required to pick up and handle the paper." Reliability concerns VVPAT systems can also introduce increased concern over reliability. Professor Michael Shamos points out that "Adding a paper printing device to a DRE machine naturally adds another component that can fail, run out of ink, jam or run out of paper. If DREs are alleged already to be prone to failure, adding a paper trail cannot improve that record." In Brazil in 2003, where a small number of precincts had installed paper trails, failure of the printers delayed voters by as much as 12 hours, a figure that would be catastrophic in the U.S. Current implementation of VVPAT systems use thermal printers to print their paper ballot records. Ballot records printed on the thermal paper will fade with time. Also, heat applied to the paper before or after the election can destroy the printing. Implementation concerns It can be significantly more difficult to implement a VVPAT as an after-the-fact feature. For jurisdictions currently using direct recording electronic voting machines that lack a VVPAT, implementation can be expensive to add and difficult to implement due to the specialized external hardware required. To add a VVPAT component to a DRE machine, a jurisdiction would be required to purchase the system designed by the vendor of the DRE machine with a no bid, sole source purchase contract. That assumes the vendor has designed a component that is compatible with the DRE machine in use. The vendor may not have developed a VVPAT component that is compatible with the DRE machine in use, thus requiring the jurisdiction to purchase an entirely new voting system. For jurisdictions not currently using direct recording electronic voting machines, the introduction of a new voting system that includes a VVPAT component would have less implementation challenges. Some implementations of the VVPAT place a high cognitive burden on the voter and are extraordinarily error prone. Legal questions One important question of VVPAT systems is regarding the time of the audit. Some have suggested that random audits of direct recording electronic voting machines be performed on Election Day to protect against machine malfunction. However, the partial tallying of votes before the polls have closed could create a problem similar to the occurrence in American national elections where a winner is declared based on East