Worldwide, legislation concerning the effect and validity of electronic signatures, including, but not limited to, cryptographic digital signatures, includes: In the EU, electronic signatures and related trust services are regulated by the Regulation (EU) N°910/2014 on electronic identification and trust services for electronic transactions in the internal market (eIDAS Regulation).
At the same date, any laws of EU member states that were inconsistent with eIDAS were also automatically repealed, replaced or modified.
In contract to the aforementioned directive (which allowed the EU member states to interpret it and transpose it to their own law) the eIDAS Regulation is directly effective in all member states.
(these sources are available on the LexisNexis subscription-only website) Court decisions discussing the effect and validity of digital signatures or digital signature-related legislation: Uruguay laws include both, electronic and digital signatures: Turkey has an Electronic Signature Law TBMM.gov.tr since 2004.
Turkey has a Government Certificate Authority - Kamu SM for all government agents for their internal use and three independent certificate authorities all of which are issuing qualified digital signatures.