En tu contexto, me inclino por "modify" o "amend".-

Ver el Alcaraz Varó Hughes Legal, pág. 618.-

Two possibilities. Hope this helps

G.R. No. 110120
4850 and its amendatory laws, Presidential Decree No. 813 and Executive Order No. 927, series of 1983, it is invested with the power and authority to issue ...
www.lawphil.net/judjuris/juri1994/mar1994/gr_110120_1994.ht... - 39k - Cached - Similar pages

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Note added at 7 minutos (2007-02-05 19:01:34 GMT)
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governed by law XXX and laws amending it

Oftentimes a particular law will allow for the enactment of regulations which form part of the law and which may provide more details about how a provision in the Act is applied.

Repetition in English is mandatory, particularly in legal, financial, and technical documents, thus the law that is amended has to be repeated.
Repetition in Spanish is to be avoided as much as possible, and it has all the necessary elements to do so. Thus, you have things such as el primero & el último, el mismo, la misma, éste, ésta, and their plural equivalents, as well as things like "la fecha antes mencionada" or "lo anteriormente expuesto", et al.
As a native speaker of English, I sometimes get flustered when I stumble across something like "el mismo" and I look at the preceding lines of the paragraph and come across two or three singular nouns in the masculine gender. So what am I supposed to do? Flip a coin? No, but I have to go back and read the darn thing to figure out who is who and what is what. Or I may have to go back two or three paragraphs in my wild pursuit of the original noun referred to in the first place.
Another fun thing happens when a new paragraph starts out with an object of a preposition, then comes a comma, and then a reflexive verb appears (the other passive voice in Spanish), all of which is fine in Spanish. However, a tangible subject is needed in English. The content of the object of preposition may contain the subject the translator is looking for, but concealed by the preposition. Solution: toss the preposition into the trash can and take the rest of what is left of the object of a preposition minus the preposition and convert the reflexive form of the verb into an active voice form and move on.
However, if there is no concealed subject in the object of a preposition, then you have to scramble back to preceding paragraphs and chase after the original noun referred to in the first place by that glorious "el mismo".
Another thing to watch for is a sentence in Spanish where more than one idea is lumped into the same sentence and let's say that there are three ideas jammed into one sentence. The first two are easily identified, but then the third idea starts after a comma with a verb in the gerund form. Oh man, that is just ducky! So one has to go back and dig out a subject somewhere in the preceding two ideas, along with a time sequence. Is this set of ideas cruising along in present or past tense? So the translator has to dig out a subject, define the time sequence and conjugate the verb and be on his/her way.
English has "the former" and "the latter", but we English speakers occasionally dust those off and use them, but not very much. In legal, financial, and technical language, we almost never use those two terms.
Conclusion: Repetition in this type of English is absolutely mandatory. So by all means, go ahead and repeat the name of the original law that appeared in the first place.
Hope this helps.
Next March 1st will make it 18 years of translating for Mexico City accounting firms, financial entities, banks, money laundering projects for the US Treasury Department, etc.