The procedure for translating to legal equivalence
The procedure for translation to legal equivalence differs from country to country. The standards of translation in Poland are regulated by a relevant department of the Ministry of Justice and every translator wishing to provide such services must pass a formal examination. Afterwards such a person is recognized as a 'sworn' translator - just like in Mexico. However, for ordinary translations (business, administration, and correspondence) it is enough to have an independent expert in the field. Spain, only sworn translators can do a sworn translation in Spain. To become a sworn translator in Spain you need to pass an exam by the Spanish Ministry of Foreign Affairs and Cooperation. Passing that exam allows you to apply for the certification as a "sworn interpreter". Then you register your stamp and signature and you communicate your rates for sworn translations to the Ministry, and they include your data in a public list of sworn interpreters.
In South Africa, the translator must be authorized by the High Court, and must use an original (or a sworn copy of an original) in his physical presence as his source text. The translator may only swear by his own translation. There is no requirement for an additional witness (such as a notary) to attest to the authenticity of the translation.