Tănase v. Moldova, No. 7/08, ECtHR (Grand Chamber), 27 April 2010

Inability of persons with multiple nationality to stand as candidates in parliamentary elections.

Art. 3, Prot. 1 ECHR

1. In those countries where the possession of dual or multiple nationality is permitted, this should not be a ground for ineligibility, even when the population is ethnically diverse and the number of elected persons with dual or multiple nationality may be high. However, a different approach could be justified when special historical or political considerations make a more restrictive practice necessary, without constituting a violation of Art. 3 Prot. 1 ECHR. 

2. When restrictions on the right to vote are introduced only in respect of part of the citizens and if these measures operate exclusively, or mainly, to the disadvantage of the opposition, preventing it from exercising a political role, this constitutes a violation of the right to free elections.
(The plaintiff, a well-known Moldovan politician, held dual citizenship: both Moldovan and Romanian. In 2008, with the introduction of the new electoral law requiring only Moldovan nationality to hold political office, the applicant was prevented from taking office as a Member of Parliament until he renounced his Romanian citizenship).