At least five convicted felons secured management positions at a manufacturer of electronic voting machines, according to critics demanding more stringent background checks for people responsible for voting machine software. Voter advocate Bev Harris alleged Tuesday that managers of a subsidiary of Diebold Inc., one of the country's largest voting equipment vendors, included a cocaine trafficker, a man who conducted fraudulent stock transactions, and a programmer jailed for falsifying computer records. The programmer, Jeffrey Dean, wrote and maintained proprietary code used to count hundreds of thousands of votes as senior vice president of Global Election Systems Inc. Diebold purchased GES in January 2002. According to a public court document released before GES hired him, Dean served time in a Washington correctional facility for stealing money and tampering with computer files in a scheme that involved a high degree of sophistication and planning." The former GES is Diebold's wholly owned subsidiary, Global Election Management Systems, which produces the operating system that touch-screen voting terminals use. Computer programmers say software bugs, hackers or electrical outages could cause more than 50,000 touch-screen machines used in precincts nationwide to delete or alter votes.