How long is a year? We are not the first to confront this question. See, e.g., British Calendar Act, 1751, 24 Geo. 2 c. 23 (Eng.) (adopting the Gregorian calendar); Pope Gregory XIII, Inter Gravissimas (1582), reprinted in VIII Bullarum Diplo-MATUM ET PrIVILEGIORuM SANCTORUM RoMAN-Pontifioum 386 (Sebastiano Franco & Henrico Dalmazzo, eds. 1863), translation available at http://personal.ecu.edu/ mcear-tyr/intGrvEng.html (declaring the modern, or Gregorian, calendar, in which years begin January 1 and end December 31). Following our august predecessors, we hold that a year, other than a leap year, is 365 days. In this case, concerning whether an alien has been here long enough to be eligible for discretionary relief, that conclusion means we must grant the petition for review.
I
Certain aliens subject to removal from the United States are eligible, in the discretion of the Attorney General, for “cancellation of removal,” permitting them to stay in this country. Petitioner Melquiades Lagandaon seeks to establish eligibility for this form of relief. As he was never a permanent resident of the United States, his eligibility for cancellation of removal is governed by 8 U.S.C. § 1229b(b)(l):
Attorney General may cancel removal of, and adjust to the status of an alien lawfully admitted for permanent residence, an alien who is inadmissible or deportable from the United States if the alien—
(A) has been physically present in the United States for a continuous period of not less than 10 years immediately preceding the date of such application;
(B) has been a person of good moral character during such period;
(C) has not been convicted of an offense under section 1182(a)(2), 1227(a)(2), or 1227(a)(3) of this title (except in a case described in section 1227(a)(7) of this title where the Attorney General exercises discretion to grant a waiver); and
(D) establishes that removаl would result in exceptional and extremely unusual hardship to the alien’s spouse, parent, or child, who is a citizen of the United States or an alien lawfully admitted for permanent residence.
*986
Lagandaon was personally served with a Notice to Appear (Notice) for removal proceedings on May 13, 1997. By statute, any period of continuous presence stops running when a Notice is served. § 1229b(d)(1); see
also Vasquez-Lopez v. Ashcroft,
The immigration judge (IJ) found that Lagandaon would have qualified for and, as a matter of discretion, would have received cancellation of removal, except that he hаd not been present for the requisite ten years. The IJ found that Lagandaon satisfied the requirements of § 1229(b)(1)(B)-(D) because, inter alia, he and his wife have a seriously disabled American-eitizen daughter who would suffer exceptional and extremely unusual hardship if her parents had to leave the country. Lagandaon’s wife, who did not leave the United States with him in 1987, was granted cancellation of removal.
On appeal, one member of the Board of Immigration Appeals (BIA) affirmed. The BIA held that Lagandaon needed to accrue ten years of presence “рrior to” the date the Notice was served in order to be eligible for cancellation of removal. Because the Notice was served on the 365th day of the tenth year, the BIA reasoned, he did not have ten years’ presence before the day the Notice was served.
Lagandaon petitions for review of the BIA’s eligibility determination. As the Notice was served after the effective date of the Illegal Immigration Reform and Immigrant Responsibility Act of 1996 (IIRIRA), Pub.L. 104-208 div. C., 110 Stat. 3009-546, this case is governed by IIRI-RA’s permanent rules. Under those rules, the scope of our review in a cancellation of removal case is limited.
See Romero-Torres v. Ashcroft,
The BIA’s interpretation of the Immigration and Naturalization Act (INA) is not, however, a “judgment” review of which is precluded, as it entails no exercise
*987
of discretion.
Ramirez-Perez v. Ashcroft,
II
We review purely legal questions concerning the meaning of the immigration laws
de novo. Murillo-Espinoza v. INS,
The BIA’s interpretation of § 1229b misreads the statute’s plain language by conflating twо distinct statutory provisions. Accordingly, the interpretation fails at step one of the
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analysis.
See Lal v. INS,
Section 1229b(d)(1) states that the period of presence “shall be deemed to end ... when the alien is served a notice to appear” (emphasis added). In turn, § 1229b(b)(1)(A) specifies that an applicant for cancellation of removal must have accrued ten years of physical presence “immediately preceding the date of such application” (emphasis added). So the statute’s *988 plain language provides, first, that the period of physical рresence includes the date the Notice is served, and, second, that when an alien applies for cancellation of removal, the period of continuous presence must end immediately before the application is filed.
The BIA improperly imported the “preceding the date” requirement of § 1229b(b)(1)(A) into § 1229b(d)(1). Its opinion stated:
In this case, the respondent was served with a [Notice to Appear] on May 13, 1997. Accordingly, he must establish continuous physical presence in the United States for 10 years prior to that date.... [W]e find that his period of continuоus residence [ 4 ] in the United States began on May 14, 1987 .... Therefore, we conclude that the respondent is ineligible for cancellation of removal pursuant to [§ 1229b] since he failed to establish the minimum physical presence that is statutorily required for relief.
(Emphasis added). The BIA thus concluded that the date the Notice is served does not count toward the period of continuous physical presence, and that the period of continuous presence must therefore end before that date.
The Attorney General contends here that the plain language of § 1229b сompels the BIA’s conclusion. We disagree.
Section 1229b(d)(1) states that the period of continuous presence ends “when” a Notice to Appear is served, not “prior to” that service. The plain meaning of “when” is not “the day before,” any more than it is “the week before.” All the dictionaries we have examined 5 agree that “when” does not mean “prior to.” 6 See, e.g., Merriam-Webster’s Collegiate Dictionary 1345-46 (10th ed.1993) (defining “when” as “at or during which time,” “at or during the time that: while,” “just at the moment that”); XX Oxford English Dictionary 209 (2d ed.1989) (giving definitions including “At the (or a) time at which; on the (or an) occasion on which” and “At which time, on which occasion; and then. Sometimes implying suddenness: = and just then, and at that moment.”); American Heritage Dictionary 917 (3d ed.1994) (defining “when” as “At what time,” “At the time that,” and “As soon as”). Further, the fact that Congress used language in § 1229b(b)(1)(A) that does exclude the date of application from the period of presence reinforces our conclusion that its failure to use similar language in § 1229b(d)(1) means that it did not intend to exclude the date of service. We therefore conclude that § 1229b(d)(1) unambiguously cuts off an alien’s accrual of physical presence on the date on which he is served with а Notice to Appear, not the day before.
The Attorney General appears to rely for his contrary assertion regarding the calculation of the statutory period of continuous presence on the language in § 1229b(b)(1)(A), requiring that the ten
*989
years of presence end “immediately preceding the date” an alien applies for cancellation of removal. An application for cancellation and a Notice are, however, entirely distinct documents, with different consequences. Department of Justice regulаtions recognize this distinction, as they require applications for cancellation to be filed
after
jurisdiction vests in the immigration court. 8 C.F.R. § 1240.20(b). Jurisdiction vests when the Notice is filed with the court, not when it is earlier served on the alien. 8 C.F.R. § 1003.14(a);
see also Martinez-Garcia v. Ashcroft,
The BIA’s opinion cited two of its precedent cases for support. One is inapposite, and the other undercuts the BIA opinion.
Matter of Nolasco-Tofino, 22 I. & N. Dec. 632 (BIA 1999), concerned the treatment of notices to appear and their predecessors, orders to show cаuse, in cases arising under the transitional rules of IIR-IRA. Prior to IIRIRA, the application for relief ended the period of continuous presence. Under IIRIRA, the date notices or orders to show cause are served ends the period of continuous presence. The question in Nolasco-Tofino was whether IIRI-RA’s designation of the ending date applied retroactively to transitional-rule cases. Id. at 633. Lagandaon does not dispute that it is the date of service of the Notice that is dispositive here, and this is a permanent, not a transitional, rules case. Nolasco-Tofino therefore has no pertinence.
Matter of Mendoza-Sandino, 22 I. & N. Dec. 1236 (BIA 2000), stаted that the effect of § 1229b(d)(1) is to provide that “the period of continuous physical presence stops upon the service on the alien of a charging document.” Id. at 1239 (emphasis added). This statement does not support the assertion that the period stops the day before service of the charging document. Instead, Mendoza-Sandino undercuts the government’s position in this case.
We conclude that the period of continuous presence ends on the day the Notice is served. In this case, that day was May 13, 1997. We therefore include May 13, 1997 in evaluating the length of Lagandaon’s presence in this country.
*990 III
Perhaps anticipating our above holding, the government makes two additional, alternative arguments. First, the government contends that even if May 13, 1997 counts towards Langadaon’s continuous presence, Lagandaon is still one day short of ten years, and therefore statutorily ineligible for cancellation of removal. Under this argument, a year of continuous physical presence accrues only when an alien is present from a given date until that same date the subsequent year. Thus, because the ten year period began on May 14, 1987, Lagandaon would have to have been present until May 14, 1997 to satisfy the requirement. Second, the government contends that еven if May 13, 1997 counts towards Lagandaon’s continuous presence, he is still statutorily ineligible for cancellation of removal because he is at least several hours short of ten years. Under this argument, a year of continuous physical presence begins at a certain time on a given date and ends just after that time on the 365th day thereafter. Under that approach, to satisfy the ten year requirement Lagandaon would have had to have been present from whatever time he arrived on May 14, 1987 until slightly after that time on May 14,1997.
As an initial matter, it is not clear that the BIA’s opinion actually relied on either of the Attorney General’s alternative arguments. If anything, the BIA’s opinion suggests that the Board thought that ten years had accrued on May 13. Had it believed otherwise, it probably would not have stressed that the ten year period had to accrue before May 13.
This state of affairs raises a question as to whether
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analysis is appropriate. We cannot defer to an agency “when its path of reasoning is not clear.”
Nat’l Ass’n of Home Builders v. Norton,
In the end, we need not decide whether deference is required. Although the statute’s meaning may not be absolutely plain at first glance, the traditional tools of statutory construction allow only one reasonable interpretation. That interpretation is contrary to either of the versions urged upon us by the government.
To determine what would constitute ten years of continuous presence, we must first consider what one year of continuous presence would be. The parties both advance theories that a year of presenсe should be counted from the moment of arrival in the United States.
8
With very limited exceptions, however, common law legal systems have long reckoned periods of legal significance by the calendar, not
*991
by the clock.
See Mason v. Bd. of Educ.,
Hence, standard legal references define a “year,” the term we are attempting to understand, in terms of dates.
Black’s Law Dictionary
1609 (7th ed.1999) defines a year as “[tjwelve calendar months beginning January 1 and ending December 31,” or as “[tjwelve calendar months beginning at any point.” With only
Black’s
as our guide, it would be plain that the period from May 14, 1987, to May 13, 1988, constituted one year (and so that from May 14, 1987, to May
18,
1997, ten).
See also, e.g., Bailey v. Faux,
It was, indeed, in order to avoid calculating precise times that the law pressed into wide use the span of time called “a year and a day.” For example, a year and a day was the period during which a victim had to die in order for his assailant to be charged with murder. 9 Rather than count a full year from the moment of the attack to the moment of death, it was deemеd more convenient to count the whole day of the lethal blow, but then append an extra day to the legally significant interval. Lord Coke explained:
If the stroke, or poyson, & c. be given the first day of January, the year shall end the last day of December: for though the stroke, or poyson, & c. were given in the afternoon of the first day of January, yet that shall be accounted a whole day, for regularly the law maketh no fraction of a day: and the day was added [ie., the rule became a year and a day, rather than a year], that there might be a whole year at the lеast after the stroke, or poyson, & c.
3 Edward Coke, Institutes of the Laws of England 53 (photo, reprint 1986) (1797 ed.);
see also State v. Brown,
Congress is presumed to legislate against the background of the common law.
Astoria Fed. Sav. & Loan Ass’n v. Solimino,
The government does not dispute that the day of Lagandaon’s arrival in the United States is to be included as a part of his period of physical presence. Traditionally, the first day is included in reckoning a specific period of time.
See Arnold v. United States,
In
Griffith v. Bogert,
Whether the terminus a quo should be so included, it must be admitted, has been a vexed question for many centuries, both among learned doctors of the civil law and the courts of England and this country. It has been termed by a writer on civil law (Tiraqueau) the contr-oversia controversissima.
In common and popular usage, the day a quo has always been included, and such has been the general rule both of the Roman and common law. The latter admits no fractions of a day; the former, in some instances, as in cases of minority, calculated de momento en momentum. The result of this subdivision was to comprehend a part of the terminus a quo. But in cases where fractions of a day were not admitted, as in those of usucaption or prescription, a possession commencing on the 1st of January, and ending on the 31st of December, was counted a full year. It was in consеquence of the uncertainty introduced on this subject by the disquisitions and disputes of learned professors, that Gregory IX., in his decretals, introduced the phrase of “a year and a day,” in order to remove the doubts thus created, as to whether the dies a quo should be included in the term. It thus maintained the correctness of the common usage, while it satisfied the doubts of the doctors.
Id. at 162-63. Deeming the terminus a quo inclusive, and counting eighteen months in the same manner as one would count a year from January 1 to December 31, the Court determined that the eighteen months beginning November 1, 1819, had run on April 30, 1821.
This case is congruent with
Griffith.
As in that case, the first legally significant date, the
terminus a quo,
is included. As
Black’s
and Coke clearly explain, and
Griffith
holds, a year runs from one date to the
piior
date in the nеxt year — 365 days, the equivalent of the period from January 1 to December 31, and
not
that from January 1 to the next January 1, which would be 366 days, or a year and a day.
10
See, e.g., Irving v. Irving,
*993
Absent any indication that Congress meant to exclude the day of the alien’s arrival from the period of physical presence accrued, the day should therefore be included. The statute does not, after all, fix a date upon which an alien becomes eligible for cancellation of removal, but rather defines an interval of time. No reason has been suggested for why this span of time wоuld run only from the day
after
an alien’s arrival. If there were any doubt, the canon of construction according to which statutory ambiguities are construed in favor of aliens would counsel strongly in favor of including the date of arrival.
See INS v. Cardozo-Fonseca,
To be sure, this reading of the statute allows some aliens, like Lagandaon, to establish ten years of presence while not having been in the United States for every single moment of what might be thought ten
full
years. However, this problem was recognized as long ago as the thirteenth century, leading to the innovation of the “and a day” concept.
See State v. Rogers,
IY
Because the BIA erred in determining that Lagandaon was statutorily ineligible for cancellation of removal by virtue of the physical-presence requirement, we GRANT the petition for review and REMAND for the BIA to determine whether Lagandaon should, as a matter of discretion, receive the relief for which he is statutorily eligible. We note again that the IJ stated he would have granted such relief but for his erroneous view of Lagan-daon’s eligibility.
Notes
. The Notice to Appear gives the date of Lagandaon's last arrival in the United States as July 31, 1988. The parties agree, however, and the Board of Immigration Appeals found, that Lagandaon was absent from the United States in 1988 for only twеnty days. An absence of that length does not interrupt a period of presence for purposes of cancellation of removal eligibility.
See
§ 1229b(d)(2) (allowing aliens to be absent for up to ninety days at a time, up to a total of 180 days, without disrupting a period of continuous presence for purposes of cancellation eligibility);
see also Vasquez-Lopez v. Ashcroft,
As of March 1, 2003, the INS no longer exists, and its functions have been transferred to the Department of Homeland Security. See Homeland Security Act of 2002, Pub.L. 107-296, § 471, 116 Stat. 2135; 6 U.S.C.A. § 542 note (West 2004). We nonetheless refer to the INS, as it was the agency involved in Lagandaon’s earlier proceedings.
. We have also indicated that nonprecedential BIA decisions might receive less deference than those designated as precedential.
Padash v. INS,
. The Supreme Court has indicated that courts may not owe full
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deference to an agency charged with adjudicating issues under a statute when a different agency is charged with enforcement of the statute.
See, e.g., Martin v. OSHRC,
.Continuous residence of seven years is required for permanent residents seeking cancellation of removal. § 1229b(a)(2). As he was not a permanent resident, Lagandaon’s burden was to show his presence, not residence, for ten years. § 1229b(b)(1)(A). We assume that the BIA's reference to residence instead of presence was inadvertent, and our decision does not turn on that error.
. Dictionaries can aid in applying step one of the
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analysis.
See MCI Telecomms. Corp. v. AT & T Co.,
. One idiomatic exception, not here pertinent, exists in which "when” can mean "at a former and usu[ally] less prosperous time,” Merriam-Webster’s at 1345-as in, "I knew him when!”
. Our reading of § 1229b(d)(1) may appear on first glance to render § 1229b(b)(1)(A)'s specification that the ten years be accrued “immediately preceding the date of such application” of little consequence, in light of the inevitable delays between service of a Notice and the date on which an alien can apply for cancellation. Our interpretation does not, however, render the language in question in § 1229b(b)(1)(A) empty. “[[Immediately preceding the date of such application” requires that the ten-year period be the period of presence — from among all the times the alien was in the United States' — that immediately preceded the application. The provision thus rules out claims where aliens seek to rely on periods of physical presence not continuous with the period of presence during which they were placed in removal proceedings. For example, if an alien was present in the United States from 1968-1980, absent, and then present again from 2000 until being served with a Notice in 2004, the phrase "immediately prior to” in § 1229b(b)(l)(A) forecloses her reliance on her presence in the 1970s to establish eligibility for cancellation now.
. The Attоrney General contends that the year closes on that same moment of arrival on the same date of the following year, while Lagan-daon contends that the year closes on the same moment of the prior date of the following year. The difference is that counting from, say, 10 a.m. on January 1 to 10:01 a.m. the next December 31 would only require presence for 364 days and a fraction, whereas counting from 10 a.m. January 1 to 10 a.m. the next January 1 would make for one "full” year of 365 twenty-four-hour days.
After suggesting the former interpretation, Lagandaon notes that one cannot tell from the record when he arrived on May 14, 1987, and posits that the burden of proof on this question lies with the government. The government responds that, even assuming that 364 days and one second would be enough, Lagandaon would have the burden of establishing the time of his arrival and service. As we reject any interpretation on which the time of those events would matter, we do not reach the burden of proof question.
. Less well known is the rule that a serf who remained fugitive in a free town for a year and a day would have his freedom.
See Dred Scott v. Sandford,
. Of course, in leap years, one additional day would be added. See 2 Blackstone, supra, at 140 ("[T]he increasing day in the leap-year, together with the preceding day, shall be accounted for one day only.”).
. For some purposes, we do exclude the date of an event from the calculation of a period of
*993
time running from that evеnt. But that is so when the relevant rule explicitly so states. For example, Federal Rule of Civil Procedure 6(a) provides: "In computing any period of time ... the day of the act, event, or default from which the designated period of time begins to run shall not be included."
See generally
J.A. Bock,
Inclusion or Exclusion of First and Last Days in Computing the Time for Performance of an Act or Event Which Must Take Place a Certain Number of Days Before a Known Future Date,
. The use of “and a day” (or “and one day”) to ensure that counting the day a quo will not result in a period shorter than one full year is not limited to one year and a day. See, e.g., Cal. Penal Code § 194 (West 1999) (amended in 1969 to change the common-law year and a day rule to three years and a day); Mo. Rev. Stat. § 142.881.10 (2003)(allowing certain bonds to be held for three years and a day); id. § 326.310.3 ("[T]he board may provide that the person shall not apply for a new license for a maximum of three years and one day following the date of the order of revocation.”); N.J. Stat. Ann. § 34:7-3 (West 2003) (allowing certain records to be destroyed after three years and one day); S.C. Code Ann. § 12-28-1175(C) (Law Coop 2003) (allowing deposit to be retained for three years and one day).
. The legislative history of § 1229b is unilluminating.
See
H.R.Rep. No. 104-469,
