If the voter plaintiffs receive a preliminary injunction, a total of 57 affected counties could still hold their November elections using paper ballots with optical scan readers.

The voters argue that computerized voting systems are vulnerable to tampering and malfunctions. There is no independent record allowing voters to verify their own votes or election officials to recount votes if necessary.

The complaint details breakdowns and loss of votes by machines that have been certified for use in Pennsylvania by the secretary of state, according to a release.

Incidents cited include the loss of votes in four precincts in Berks County last year, 10,000 votes in three Pennsylvania counties that were not counted in the 2004 presidential election, and 200 machines in Philadelphia that experienced problems in the May 2006 primary.

With the all-electronic voting systems certified by the secretary of state, it’s impossible to ensure all votes are recorded and counted as intended by the voters, said Michael Churchill, co-counsel for the plaintiffs and attorney with the Public Interest Law Center of Philadelphia (PILCOP).