What does "may" mean when used as a verb in a text of law in the US? Possibility or guarantee?

Question

What does "may" mean when used as a verb in a text of law in the US?

For example, if the law say "X may do Y", is it guaranteed that X can do Y, or does that mean that perhaps the judge or whoever has the decision power will grant the X the right to do Y, but not this isn't sure at all?

Actual example from 8 C.F.R. 316.5(c)(1)(i) (see emphasis):

(c) Disruption of continuity of residence -

(1) Absence from the United States -

(i) For continuous periods of between six (6) months and one (1) year. Absences from the United States for continuous periods of between six (6) months and one (1) year during the periods for which continuous residence is required under § 316.2 (a)(3) and (a)(6) shall disrupt the continuity of such residence for purposes of this part unless the applicant can establish otherwise to the satisfaction of the Service. This finding remains valid even if the applicant did not apply for or otherwise request a nonresident classification for tax purposes, did not document an abandonment of lawful permanent resident status, and is still considered a lawful permanent resident under immigration laws. The types of documentation which may establish that the applicant did not disrupt the continuity of his or her residence in the United States during an extended absence include, but are not limited to, evidence that during the absence:

(A) The applicant did not terminate his or her employment in the United States;

(B) The applicant's immediate family remained in the United States;

(C) The applicant retained full access to his or her United States abode; or

(D) The applicant did not obtain employment while abroad.

In this example, if one satisfies A, B, C, or D, is one guaranteed not to disrupt the continuity of my residence for the purpose of naturalization?

Answer 1

"May" means "is possible" and not "is necessary". The specific law does not say anything about a person doing A, B or C and it does not say that if you do one of A, B or C then something mandatorily follows. It asserts that certain types of documentation "can" be used as evidence supporting the proposition that the applicant did not disrupt continuous residence, but it also asserts (without giving any further hints) that other things may be used. This law does not state necessary or sufficient conditions for establishing undisrupted continuous residence. It is not hard to construct a scenario where a person moves back to their home country and ran for public office there, but failed to quit the US job. In light of compelling evidence that they actually moved back home, failure to quite your US job is not proof that you remained in the US. Proof resides in the totality of evidence, not just the admissibility of a single fact. Doing one or more of (A-D) is no guarantee of anything.

Answer 2

In this case, "may" indicates possibility. The point of this list is illustrative. Using may clarifies that presenting these documents (and others like them) will not guarantee the success of the application. The reason for the hedging, in this case, is to underscore that the determination in question cannot be made mechanistically based on any particular circumstance or documentation of that circumstance.

With that in mind, your specific questions:

is it guaranteed that X can do Y, or does that mean that perhaps the judge or whoever has the decision power will grant the X the right to do Y

Well, yes, X can do Y, but it is certainly not guaranteed that X necessarily will do Y. In this case, even an applicant presents evidence of all four items A through D, there could be other circumstances that point to a finding that the applicant's continuity of residence was in fact interrupted.

if one satisfies A, B, C, or D, is one guaranteed not to disrupt the continuity of my residence for the purpose of naturalization?

Not at all. Consider what would happen if it did create such a guarantee: a wealthy applicant could maintain an abode in the US and return to it for one day every 364 days, thereby claiming continuity of residence over a period of 5 years while having spent only 5 days in the US.

This regulation provides guidance for a subjective determination; there is no guarantee of anything.

Answer 3

The use of “may” versus “shall” or “will” indicates that it is NOT mandated to happen.

“Shall” and “will” when found in law, is a command that must happen, while “may” may or may not happen. The use of “may” indicates that discretion to act is being granted rather than a command to act. Let’s look at the example above.

Section 8 Code of Federal Rules (C.F.R.) 316.5(c)(1)(i).

It states in part:

“(i) For continuous periods of between six (6) months and one (1) year. Absences from the United States for continuous periods of between six (6) months and one (1) year during the periods for which continuous residence is required under § 316.2 (a)(3) and (a)(6) shall disrupt the continuity of such residence for purposes of this part unless the applicant can establish otherwise to the satisfaction of the Service.”*

Here “shall” is used to command that the continuity period is broken, and so the person must start all over again. NO discretion is given.

It continues:

“The types of documentation which may establish that the applicant did not disrupt the continuity of his or her residence in the United States during an extended absence include, but are not limited to, evidence that during the absence:

(A) The applicant did not terminate his or her employment in the United States;

(B) The applicant's immediate family remained in the United States;

(C) The applicant retained full access to his or her United States abode; or

(D) The applicant did not obtain employment while abroad."

“shall” used here indicates that these docs may be used to find that continuity has been preserved, but it is not mandated that they do. The agency should look at all the factors present in making its decision to end continuity.

If it stated:

The types of documentation which will establish that the applicant did not disrupt the continuity…

or

The types of documentation which shall establish that the applicant did not disrupt the continuity...

If “will” or “shall” were used instead of “may”, then the agency would have been commanded to hold that continuity was preserved based only upon these documents rather than all the facts present in the case.