I'm not sure if they've been ruled constitutional in Netherland, but in 2009 the government decided not to use them anymore after pressure from an organization called "Wij vertrouwen stemcomputers niet" ("We don't trust voting computers"), lead by hacker and pioneering ISP founder Rop Gonggrijp.
I'm actually still kind of impressed that a protest from the hacker community was so successful in convincing the government.