Kommer Kleijn, spokesman for VoorEVA.be, a Belgian organization that rejects the e-voting system because "it deprives voters from effectively verifying the elections in which they partake" called the problems "a catastrophe."
"They claim that the recording of the votes was done flawlessly, but who can verify that? We can't," Kleijn said.
There is no way to prove that the bug was only present in the application used to add up the votes and not in other parts of the voting system, he said.
And even though the source code of the software is published after the elections there is no way to verify the code beforehand, he said. Therefore VoorEVA concludes that the results of the elections in these municipalities cannot be valid and need to be redone, Kleijn said.
It is not the first time voting with this system went awry, said Kleijn. "Every time this system was used there was a fault comparable to this one," Kleijn said.
In 2003 in the town of Schaarbeek for instance voting machines counted 4,096 more votes more than there were registered voters, according to a study conducted by seven Belgian universities. And in Liège in 2006, some candidates had a higher intermediate result than their end result, said Kleijn.
While the problems are ongoing, there have been fewer problems with e-voting systems this year than in 2012, said Grouwels. On Sunday there were about 600 technical interventions needed, about one-third fewer than in 2012, he said.
Most of the interventions were small, for instance problems with card readers, printers and malfunctioning displays, according to Grouwels.
Belgium is one of the last European countries to still use e-voting systems. In Germany, the Federal Constitutional Court banned the use of electronic voting machines in 2009 because results from the machines were not verifiable. The Netherlands banned the practice in 2008 after a group of activists successfully demonstrated that both types of electronic voting machines then in use could be tampered with.
There are still some municipalities in France that use electronic voting machines, though, and Estonia uses an Internet e-voting system that security and Internet voting researchers found vulnerable to several attacks and said shouldn't be used for the European elections.
The researchers' claims, published two days before the beginning of online balloting for elections to the European Parliament, gave the Estonian National Electoral Committee (ENEC) no reason to suspend online balloting, the committee said at the time.
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