2002: Germany, Legal Recognition of German Sign Language
"German Sign Language or Deutsche Gebärdensprache (DGS), is the sign language of the deaf community in Germany and in the German-speaking community of Belgium. The language has evolved through use in deaf communities over hundreds of years.
German Sign Language was first legally recognised in The Federal Disability Equality Act (2002) in May 2002. Since then, deaf people have a legal entitlement to Sign Language interpreters when communicating with federal authorities, free of charge."
Source: https://en.wikipedia.org/wiki/German_Sign_Language
Source: http://wfdeaf.org/news/the-legal-recognition-of-national-sign-languages/