It is absolutely okay that a number of English words have more than one meaning (e.g. watch). It is also absolutely okay that a number of legal English terms have more than one meaning (e.g. enfranchisement – US/UK human rights law and UK property law). But it is kind of strange that a legal term should have two meanings that are contradictory to one another, depending on the context. It's like meaning black in one text and white in another one.
As Black’s Law Dictionary puts it, the term SANCTION means: (i) an official approval or authorisation, solemn and final confirmation OR (ii) a provision that gives force to a legal instrument by either rewarding obediance or punishing disobedience. In short, it can either mean APPROVAL or PUNISHMENT.
Now let us see how this term and its two contradictiory meanings work in practice. Let us have some examples to illustrate it:
(i) Example one:
”A probation agency may use administrative sanctions to address a technical violation committed by a defendant.”
Obviously, it is the punishment sense. (If you wish to learn how to use the term ”sanction” in the punishment sense, the sentence pattern is: ”entity + use + sanction + to address + violation + by person”).
(ii) Example two:
"Section 563.031.1 sanctions the use of physical force to defend oneself against an imminent and unlawful attack."
It is the approval sense (verb form). (The sentence pattern is: ”instrument + sanction + use + of item”).
(iii) Example three:
”The statutory mosaic gives the Board the power to investigate, prosecute, adjudicate and sanction members of the medical profession for "unprofessional conduct" as defined by § 5-37.1-5 of the Act.”
Obviously, it is the punishment sense again (verb form). (The sentence pattern is: ”entity + sanction + person + for wrong”).
(iv) Example four:
"Our approval of any Superior Court rule means only that this court must give its sanction to any rule which modifies the Federal Rules of Civil [or Criminal] Procedure."
It is the approval sense again (in the noun form). (The sentence pattern is: ”court + give + sanction + to instrument”).
(v) Example five:
"This state doesn't sanction the use of medicinal marijuana."
Now what does it mean?
Does the state approve or punish the use of this controlled substance? In other words, can I use this substance freely or will face prison if I do so?
The above examples clearly demonstrate that the meaning of the term depends
on the context, and on the sentence patterns this term is used in.
It is clear that if you wish to use this term in your own writing or in translation properly and in line with your intentions (and not the other way round), these sentence patterns must be learnt.
These two meanings of the term "sanction" are described in separate chapters in the book entitled ”A Practical Guide to English for Law”. The approval sense is covered in Chapter 21 entitled "Permitting and approving" while the punishment sense is covered in Chapter 42 entitled "Sanctioning and punishment" in MUCH more detail (in a total of four pages), so that you can use this widely used term in a delicate manner, in line with your intentions.
Finally, in an answer to the question put for example five, let us have the context:
”Because your state doesn't sanction the use of medicinal marijuana, it is illegal to use it in that state, no matter the purpose, and no matter where you bought it.”
So it is the approval sense again. The sentence pattern to learn – as native professionals are well aware of it, so you must be also if you wish to attain proficiency in legal English – is: ”entity + sanction + use + of item”.
The book describes a total of 1550 terms to be found in legal texts, in 8000+ sentence patterns, in 800 overview tables and in 50 chapters to assist you in your pursuit to attain excellence in legal English.