Baybasin v. The Netherlands, No. 13600/02, ECtHR (Third Section), 6 July 2006 

Prohibition imposed on prisoner from using their mother tongue in conversations with his family members. No breach of the right to respect for private and family life.

Arte 8 ECHR

Whilst it is an essential part of a prisoner’s right to respect for family life that the prison authorities should assist him in maintaining contact with his family, the Court recognises at the same time that some measure of control over prisoners’ contacts with the outside world is called for and is not of itself incompatible with the Convention.
The circumstance that all correspondence and telephone calls of detainees are screened for security reasons, and, in order to enable an adequate supervision of such contacts, detainees are only allowed to use a limited number of specifically designated languages, cannot be considered un unreasonable balance between the applicant’s right to respect for his family life and the authorities’ interest in maintaining the strict security rules, expecially if it has not been established that it would be impossible for the applicant to any other permitted language in his contacts with his family.

(Case in which the Netherlands’ prison administration prohibited the applicant, inmate of Kurdish ethnicity, from conversing with family members using the Kurmanci language)