Constitutional Court of Ukraine
On 10 July 2014 57 parliamentary deputies appealed the Constitutional Court of Ukraine to review the 2012 law "On the principles of the state language policy". On 10 October 2014 the court opened the proceedings on the constitutionality of the law. On 14 December 2016 the Constitutional Court ended the oral proceedings and on 13 January 2017 moved to the closed part of the process. On 28 February 2018 the Constitutional Court of Ukraine ruled the law unconstitutional.