                  FOR PUBLICATION

  UNITED STATES COURT OF APPEALS
       FOR THE NINTH CIRCUIT


UNITED STATES OF AMERICA,               No. 16-30188
          Plaintiff-Appellee,
                                         D.C. No.
             v.                   1:15-cr-00254-BLW-1

GREGORY OBENDORF,
      Defendant-Appellant.               OPINION


      Appeal from the United States District Court
                for the District of Idaho
    B. Lynn Winmill, Chief District Judge, Presiding

        Argued and Submitted February 9, 2018
                 Seattle, Washington

                   Filed July 9, 2018

      Before: Ronald M. Gould, Richard A. Paez,
         and Morgan Christen, Circuit Judges.

              Opinion by Judge Christen
2                 UNITED STATES V. OBENDORF

                            SUMMARY*


                           Criminal Law

    Affirming a conviction for illegally baiting ducks in
violation of the Migratory Bird Treaty Act, and conspiring to
do the same, the panel held that an “agricultural practice
exception” set forth in 50 C.F.R. § 20.21(i)(1) applies to
unlawful taking, but not unlawful baiting, and thus could not
have immunized the defendant’s conduct.

   The panel concluded that although the parties
misapprehended the law in the district court by treating
§ 20.21(i)(1) as applicable to the defendant’s case, the error
was harmless.


                             COUNSEL

Greg S. Silvey (argued), Silvey Law Office Ltd., Boise,
Idaho, for Defendant-Appellant.

Varu Chilakamarri (argued), Emily A. Polachek, and Andrew
C. Mergen, Attorneys; Eric Grant, Deputy Assistant Attorney
General; Jeffrey H. Wood, Acting Assistant Attorney
General; Environment and Natural Resources Division,
United States Department of Justice, Washington, D.C.;
Christian S. Nafzger, Assistant United States Attorney;




    *
      This summary constitutes no part of the opinion of the court. It has
been prepared by court staff for the convenience of the reader.
                UNITED STATES V. OBENDORF                       3

Rafael M. Gonzalez Jr., Acting United States Attorney;
United States Attorney’s Office, Boise, Idaho; for Plaintiff-
Appellee.


                           OPINION

CHRISTEN, Circuit Judge:

    Defendant-Appellant Gregory Obendorf is an Idaho
farmer who was convicted of illegally baiting ducks in
violation of the Migratory Bird Treaty Act (MBTA),
16 U.S.C. §§ 703–712, and conspiring to do the same.
Obendorf denied that he was baiting ducks and argued that he
was simply farming his land. At trial, Obendorf sought to
cross-examine government witnesses about the propriety of
his farming practices, but the district court would not allow
the inquiry. He appeals that ruling and a jury instruction. We
have jurisdiction under 28 U.S.C. § 1291, and we affirm
Obendorf’s conviction.1

                      BACKGROUND

                                I.

    Obendorf’s farm lies just north of the Boise River, near
the town of Parma, Idaho. Hundreds of thousands of ducks
pass by the farm during their annual migration each fall. One
of Obendorf’s fields is about fifteen acres in size and planted
with corn. It has come to be known as the duck field, and it
figures prominently in this case.

    1
      We resolve Obendorf’s other challenges to his conviction and
sentence in a concurrently filed memorandum disposition.
4              UNITED STATES V. OBENDORF

    A few times a year, federal agents from the U.S. Fish and
Wildlife Service (FWS) patrol the river valleys of
southwestern Idaho by airplane, looking for signs of
waterfowl baiting. On November 15, 2013, FWS Special
Agent Scott Kabasa and two of his colleagues flew over
Obendorf’s farm. Such flights are routine, but Kabasa paid
special attention to Obendorf’s farm during the November 15
flight because he had received a number of tips that Obendorf
was baiting ducks on his property. As the plane passed over
Obendorf’s farm, Kabasa noticed several large piles of corn
in the duck field, including a pile near a hunting pit blind.
Kabasa also noticed the duck field had been harvested
differently from other fields on Obendorf’s farm. Most of
Obendorf’s cornfields were fully harvested, but the duck field
was “strip combined”—meaning it was harvested in
alternating strips such that many rows were left untouched.

    That night after dark, Kabasa and Brian Marek, a
conservation officer with the Idaho Department of Fish and
Game, snuck onto Obendorf’s farm to take a closer look.
Kabasa and Marek counted six large piles of loose corn
kernels on the duck field, including one “within shot-shell
range” of the pit blind. They also inspected the strip-
combined rows in the duck field and observed “an exorbitant
amount” of corn kernels littering the ground under the stalks.
Kabasa later testified that “the vastness of the corn that was
on the ground was unbelievable.” The agents walked
Obendorf’s other cornfields, which, unlike the duck field,
appeared neatly combined and fully harvested. Before
leaving, the agents installed a disguised camera called a
Plotwatcher in the duck field, pointed it at the pit blind, and
programmed it to take and store photographs every few
seconds.
               UNITED STATES V. OBENDORF                     5

    State and federal officials returned to Obendorf’s farm
several more times in the ensuing weeks. On one trip, Kurt
Stieglitz, an investigator with the Idaho Department of Fish
and Game, installed a second Plotwatcher. Investigators
spoke with several current and former Obendorf employees
about Obendorf’s activities in the duck field. Investigators
also met with Obendorf several times during the
investigation. Obendorf gave Kabasa and others a tour of his
farm, including the duck field, in January of 2014. Obendorf
also reached out to Marek several times even after retaining
an attorney.

                              II.

    Nearly two years after the investigation began, Obendorf
was charged in a two-count indictment. The first count
alleged that Obendorf conspired over several years to bait the
duck field and lure ducks for hunting by directing his
employees to harvest the duck field wastefully, in violation of
18 U.S.C. § 371 (the general federal conspiracy statute). The
second count charged Obendorf with baiting the duck field in
November of 2013 to facilitate hunting in the same fashion,
in violation of 16 U.S.C. § 704(b)(2), the anti-baiting
provision of the MBTA. Both offenses are Class A
misdemeanors. See id. § 707(a), (c); 18 U.S.C. §§ 371,
3559(a)(6).

    The indictment also introduced a wrinkle that gave rise to
this appeal. In a series of paragraphs titled “Relevant Laws
and Regulations,” the indictment set forth the MBTA’s ban
on unlawful baiting, the statutory basis for FWS’s authority
to enforce the MBTA, and several regulatory definitions.
One provision cited in this section of the indictment was
6              UNITED STATES V. OBENDORF

50 C.F.R. § 20.21(i)(1)(i), which the indictment quoted in its
entirety. That regulation provides:

       Migratory birds on which open seasons are
       prescribed in this part may be taken by any
       method except those prohibited in this section.
       No persons shall take migratory game birds:

           ....

       (i) By the aid of baiting, or on or over any
       baited area, where a person knows or
       reasonably should know that the area is or has
       been baited. However, nothing in this
       paragraph prohibits:

       (1) the taking of any migratory game bird,
       including waterfowl, coots, and cranes, on or
       over the following lands or areas that are not
       otherwise baited areas—

           (i) Standing crops or flooded standing
           crops (including aquatics); standing,
           flooded, or manipulated natural
           vegetation; flooded harvested croplands;
           or lands or areas where seeds or grains
           have been scattered solely as the result of
           a normal agricultural planting, harvesting,
           post-harvest manipulation or normal soil
           stabilization practice[.]

50 C.F.R. § 20.21(i)(1)(i). The indictment also set forth in
full the regulatory definitions of terms like “normal
agricultural planting, harvesting, or post-harvest
               UNITED STATES V. OBENDORF                    7

manipulation” and “baited area.” As relevant here, whether
a practice constitutes “normal agricultural planting,
harvesting, or post-harvest manipulation” or a “normal soil
stabilization practice” turns on whether the practice is
“conducted in accordance with official recommendations of
State Extension Specialists of the Cooperative Extension
Service of the U.S. Department of Agriculture.” 50 C.F.R.
§ 20.11(g), (i).

     Obendorf’s case went to trial. Over the course of seven
days, a jury heard testimony from state and federal wildlife
agents, Obendorf employees, and local residents. As the
indictment foreshadowed, 50 C.F.R. § 20.21(i)(1) played a
central role in Obendorf’s prosecution. The government’s
trial brief characterized § 20.21(i)(1) as a potential “safe
haven” from an unlawful baiting conviction, and the district
court instructed the jury on the first day of trial that the
government had to prove “the agricultural practice
exception”—the court’s term for § 20.21(i)(1)—“does not
apply.” Consistent with that view, the prosecutor explained
to the jury during his opening statement that the MBTA
regulations create a “normal agricultural practices exception”
that allows farmers to work their land without fear of
prosecution under the MBTA, so long as their practices are in
accordance with official recommendations from State
Extension Specialists of the Cooperative Extension Service.

    The government called three State Extension Specialists
from the University of Idaho in an attempt to prove that
Obendorf did not qualify for what it referred to as
§ 20.21(i)(1)’s safe haven. All three witnesses testified that
no then-existing official recommendations of the Cooperative
Extension Service endorsed Obendorf’s farming practices.
On cross-examination, Obendorf tried to elicit an official
8               UNITED STATES V. OBENDORF

opinion regarding his farming practices, but the government
objected and argued that his questions were irrelevant and
beyond the scope of direct examination. The district court
agreed. It ruled that the “safe harbor” does not apply unless
the farmer “obtain[s] the official recommendation before . . .
engag[ing] in a practice.” In other words, the district court
ruled that any post-hoc endorsement from a State Extension
Specialist would not bring Obendorf within the safe harbor.

    The district court instructed the jury along the same lines.
For the substantive baiting count, the jury instructions
required the government to prove three elements beyond a
reasonable doubt: (1) that Obendorf baited ducks or directed
others to do the same; (2) that he did so for the purpose of
facilitating a hunt aided by bait; and (3) that the “Agricultural
Practice Exception” did not apply. The district court
instructed the jury that the so-called Agricultural Practice
Exception permits a farmer whose lands are not otherwise
baited to, among other things, scatter seeds or grains “solely
as the result of a normal agricultural planting, harvesting,
post-harvest manipulation or normal soil stabilization
practice.” The instructions also included the district court’s
temporal requirement:

        A farmer’s manipulation or practice
        constitutes a “normal agricultural planting,
        harvesting, post-harvest manipulation” or
        “normal soil stabilization practice” only if it is
        conducted according to the State Extension
        Service Specialists’ official recommendations,
        whether verbal or in writing. Those official
        recommendations must be in existence at the
        time the farmer engages in his manipulation
        or practice.
               UNITED STATES V. OBENDORF                     9

The instruction for the conspiracy count cross-referenced the
given elements of unlawful baiting, including the so-called
Agricultural Practice Exception.

   The jury convicted Obendorf on both counts and he
timely appealed.

               STANDARDS OF REVIEW

    We review de novo the district court’s interpretation of
the MBTA and its regulations. United States v. Bucher,
375 F.3d 929, 931 (9th Cir. 2004); United States v. Ani,
138 F.3d 390, 391 (9th Cir. 1998). We also review de novo
“whether a jury instruction misstated an element of a
statutory crime.” United States v. Henderson, 243 F.3d 1168,
1171 (9th Cir. 2001). If we identify an instructional error, we
will nevertheless affirm if the error was harmless beyond a
reasonable doubt. Id. We review the district court’s
evidentiary rulings for an abuse of discretion. United States
v. Decoud, 456 F.3d 996, 1010 (9th Cir. 2006). Even if we
find error, we will affirm unless the erroneous evidentiary
ruling “more likely than not affected the verdict.” Id.
(quoting United States v. Pang, 362 F.3d 1187, 1192 (9th Cir.
2004)).

                       DISCUSSION

    Obendorf argues the district court misinterpreted what it
called the Agricultural Practice Exception by imposing a
temporal requirement that the MBTA regulations do not
mandate. For the first time on appeal, the government argues
that what the district court called the Agricultural Practice
Exception—50 C.F.R. § 20.21(i)(1)—applies only to
prosecutions for illegally taking migratory game birds.
10             UNITED STATES V. OBENDORF

According to the government’s argument on appeal,
§ 20.21(i)(1) does not apply to unlawful baiting cases at all,
so even if the district court erred by imposing a temporal
requirement for obtaining recommendations from State
Extension Specialists, the error was harmless.

    We agree that § 20.21(i)(1) had no role to play in
Obendorf’s case because the indictment charged him with
baiting, rather than taking, migratory birds. By attempting to
prove that the so-called Agricultural Practice Exception did
not apply, the government assumed a heavier burden than the
law required. Having reviewed the record, we conclude that
the erroneous application of § 20.21(i)(1) to Obendorf’s case
was harmless.

                              I.

    We acknowledge that the government’s chief argument
on appeal is a new one. In the district court, the government
argued that § 20.21(i)(1) and its associated regulations
created a safe harbor, but one for which Obendorf was not
eligible because the State Extension Service had not
previously endorsed his agricultural practices. On appeal, the
government now argues that the safe harbor created by
§ 20.21(i)(1) was never available to Obendorf in the first
place because it does not apply to the charges he faced. “We
apply a ‘general rule’ against entertaining arguments on
appeal that were not presented or developed before the
district court.” In re Mercury Interactive Corp. Sec. Litig.,
618 F.3d 988, 992 (9th Cir. 2010) (quoting Peterson v.
Highland Music, Inc., 140 F.3d 1313, 1321 (9th Cir. 1998)).
But we have discretion to reach waived issues, and we
exercise that discretion in three circumstances: (1) “in the
‘exceptional’ case in which review is necessary to prevent a
                 UNITED STATES V. OBENDORF                           11

miscarriage of justice or to preserve the integrity of the
judicial process”; (2) “when a new issue arises while appeal
is pending because of a change in the law”; and (3) “when the
issue presented is purely one of law and either does not
depend on the factual record developed below, or the
pertinent record has been fully developed.” Id. (quoting
Bolker v. Comm’r, 760 F.2d 1039, 1042 (9th Cir. 1985)).

    Here, we exercise our discretion to consider whether
§ 20.21(i)(1) is applicable to unlawful baiting prosecutions
because the question is purely legal, both parties have had an
opportunity to brief the issue on appeal and address it at oral
argument, and resolving this question will serve to clarify the
law. See Mercury Interactive, 618 F.3d at 992. We have a
duty to “say what the law is,” Marbury v. Madison, 1 Cranch
137, 177 (1803), and we would shirk that duty by not
deciding whether § 20.21(i)(1) modifies the MBTA’s ban on
unlawfully baiting migratory birds, 16 U.S.C. § 704(b)(2).

                                  II.

    The MBTA is a century-old law implementing a treaty to
save migratory birds from “indiscriminate slaughter.”
Convention Between the United States and Great Britain for
the Protection of Migratory Birds, Gr. Brit.-U.S., Aug. 16,
1916, 39 Stat. 1702; see also Migratory Bird Treaty Act, ch.
128, 40 Stat. 755, 755–57 (1918) (codified as amended at
16 U.S.C. §§ 703–712).2



    2
     “The MBTA later incorporated elements of similar bilateral treaties
between the United States and Mexico, Japan, and the Soviet Union.”
United States v. Vance Crooked Arm, 788 F.3d 1065, 1070 n.3 (9th Cir.
2015) (per curiam).
12             UNITED STATES V. OBENDORF

     Three statutory provisions are relevant here. First, the
MBTA categorically bans a slew of conduct that could harm
migratory birds—hunting, capturing, killing, possessing,
selling, and more—and it authorizes the Secretary of the
Interior to promulgate regulations permitting activities that
the MBTA would otherwise prohibit, as long as those
activities are consistent with the underlying treaties.
16 U.S.C. § 703(a); see also id. § 704(a) (granting the
Secretary rulemaking authority). Second, the MBTA
separately prohibits any person from taking “any migratory
game bird by the aid of baiting, or on or over any baited area,
if the person knows or reasonably should know that the area
is a baited area.” Id. § 704(b)(1). (The statutory term “take”
means “to pursue, hunt, shoot, wound, kill, trap, capture, or
collect,” or to attempt any of those activities. 50 C.F.R.
§ 10.12.) Finally, the MBTA outlaws baiting migratory birds
so they can be hunted: it bans “plac[ing] or direct[ing] the
placement of bait on or adjacent to an area for the purpose of
causing, inducing, or allowing any person to take or attempt
to take any migratory game bird by the aid of baiting on or
over the baited area.” 16 U.S.C. § 704(b)(2).

    The crux of this case lies in the regulations implementing
these three statutory provisions. The MBTA regulations
define “baiting” and “baited area” very broadly. “Baiting” is
the “direct or indirect placing, exposing, depositing,
distributing, or scattering of salt, grain, or other feed that
could serve as a lure or attraction for migratory game birds to,
on, or over any areas where hunters are attempting to take
them.” 50 C.F.R. § 20.11(k) (emphasis added). Consistent
with the definition of “baiting,” a “baited area” is defined as
“any area on which [scattered] salt, grain, or other feed . . .
could serve as a lure or attraction for migratory game birds to,
on, or over areas where hunters are attempting to take them.”
               UNITED STATES V. OBENDORF                     13

Id. § 20.11(j) (emphasis added). Once an area has been
baited, it is considered a “baited area” that is off-limits to
hunting until ten days after all the bait is removed. Id.

    These broad definitions can create potential problems in
agricultural areas. Common farming practices inevitably
leave behind grains and other bird feed in fields, and
migratory game birds are loathe to pass up a free meal.
Because many species, including ducks, find crops like cereal
grains and corn particularly appetizing, at least one other
court has recognized that the “broad definition of baited areas
would seem to preclude the hunting of migratory waterfowl
over all agricultural areas.” M.J. Farms, Ltd. v. U.S. Fish &
Wildlife Serv., 593 F. Supp. 2d 907, 913 (W.D. La. 2008).

     Section 20.21(i)(1) attempts to remedy this problem. As
set forth above, that regulation carves out an exception to the
MBTA’s ban on hunting over baited areas. See Migratory
Bird Hunting: Regulations Regarding Baiting and Baited
Areas, 64 Fed. Reg. 29,799, 29,800–01 (June 3, 1999)
(discussing how the regulatory scheme seeks to harmonize
hunting and certain agricultural practices). Section 20.21(i)(1)
provides that, notwithstanding the general prohibition on
hunting over bait, nothing prohibits “the taking of any
migratory game bird” on or over “[s]tanding crops or flooded
standing crops (including aquatics); standing, flooded, or
manipulated natural vegetation; flooded harvested croplands;
or lands or areas where seeds or grains have been scattered
solely as the result of a normal agricultural planting,
harvesting, post-harvest manipulation or normal soil
stabilization practice.” 50 C.F.R. § 20.21(i)(1)(i). This
exception applies so long as the listed areas are “not
otherwise baited.” Id. In other words, farms are not exempt
from the MBTA simply because they are farms. If grain is
14             UNITED STATES V. OBENDORF

scattered as part of a farm’s normal agricultural activities and
migratory birds happen to be drawn to it, the birds are fair
game. But if grain is scattered for the purpose of baiting, the
birds may not be taken.

    The parties agree that § 20.21(i)(1) permits hunting over
agricultural lands that might otherwise be off-limits. What
they disagree about—and what we must decide—is whether
§ 20.21(i)(1) also modifies the MBTA’s ban on unlawful
baiting. We conclude it does not.

    We begin with the plain language of the regulation.
United States v. Bibbins, 637 F.3d 1087, 1091 (9th Cir.
2011); United States v. Bucher, 375 F.3d 929, 932 (9th Cir.
2004). By its terms, § 20.21 applies only to takings—that is,
hunting, shooting, and similar activities. See 50 C.F.R.
§ 20.21; see also id. § 10.12 (defining “take”). Section 20.21
provides that migratory game birds “may be taken by any
method except those” it specifically prohibits. It then goes on
to identify specific hunting methods that are illegal, like
targeting migratory game birds with machine guns or
explosives. See, e.g., 50 C.F.R. § 20.21(a). Notably, the
regulation is titled “What hunting methods are illegal?” Id.
§ 20.21 (emphasis added).

      Consistent with § 20.21’s overall focus on prohibited
hunting methods, § 20.21(i)(1) concerns only hunting over
bait—not baiting by itself. Section 20.21(i) makes plain that
hunting over bait is an illegal hunting method, mirroring the
Act’s statutory prohibition. Compare 50 C.F.R. § 20.21(i)
(“No persons shall take migratory game birds . . . [b]y the aid
of baiting, or on or over any baited area . . . .”), with
16 U.S.C. § 704(b)(1) (“It shall be unlawful for any person to
. . . take any migratory game bird by the aid of baiting, or on
               UNITED STATES V. OBENDORF                   15

or over any baited area . . . .”). The next subsection,
§ 20.21(i)(1), allows hunting over specified lands that would
otherwise seem to qualify as “baited areas.” 50 C.F.R.
§ 20.21(i)(1). Taken together, this arrangement does not alter
what it means to bait a field, but it tells hunters where they
cannot hunt, before carving out some otherwise-off-limits
areas where they can.

     The format of this regulatory scheme also points to the
conclusion that § 20.21(i)(1) does not create an exception to
the Act’s ban on unlawful baiting, and applies only to
unlawful hunting. Chapter I of Title 50 of the Code of
Federal Regulations houses a variety of FWS regulations, and
the MBTA regulations reside in Part 20 of Subchapter B. The
first provision of Part 20 states that “[t]he regulations
contained in this part relate only to the hunting of migratory
game birds.” 50 C.F.R. § 20.1(a) (emphasis added).
Section 20.21 is located within Subpart C of Part 20—titled
“Taking”—alongside restrictions on hunting seasons and how
many birds may be taken in a single day. See id.
§§ 20.20–.26.

    Finally, the legislative history of the MBTA and the
history of the regulations that implement it confirm our
reading. Until 1998, unlawful baiting was not a discrete
offense under the MBTA. See Migratory Bird Treaty Reform
Act of 1998, Pub. L. No. 105-312, § 102, 112 Stat. 2956,
2956. Yet a version of § 20.21(i) existed even before
unlawful baiting was separately outlawed. See Migratory
Bird Hunting: Regulations Regarding Baiting and Baited
Areas, 64 Fed. Reg. 29,799, 29,803 (June 3, 1999); see also
United States v. Adams, 174 F.3d 571, 574 (5th Cir. 1999)
(analyzing an earlier version of 50 C.F.R. § 20.21(i)). It
would be difficult to conclude that § 20.21(i) and any of its
16                UNITED STATES V. OBENDORF

subsections create an exception to the MBTA’s ban on
unlawful baiting because the regulation existed in
substantially the same form before baiting became a separate
crime.3

    Obendorf argues that our interpretation of § 20.21(i)(1)
would lead to an absurd result because a person could avoid
prosecution for hunting over a farmer’s field by finding
refuge in § 20.21(i)(1), but the farmer could still be
prosecuted for baiting the same field even though he or she
was simply farming the land. His fear is misplaced. To
convict a person of unlawful baiting, the government must
prove that defendant placed bait “for the purpose of causing,
inducing, or allowing any person to take or attempt to take
any migratory game bird by the aid of baiting.” 16 U.S.C.
§ 704(b)(2) (emphasis added). The Act’s mens rea
requirement ensures that innocent farmers are not ensnared.

    In sum, we conclude that 50 C.F.R. § 20.21(i)(1) does not
create a so-called Agricultural Practice Exception to the
MBTA’s ban on unlawful baiting; it instead permits hunting
over certain lands that would otherwise be off-limits.4

     3
         Obendorf suggests FWS simply forgot to account for the change
when it updated its regulations, but FWS published a notice of its rule
change in the Federal Register that explicitly acknowledged the
amendment. See Regulations Regarding Baiting, 64 Fed. Reg. at 29,800
(“[I]t is now a separate offense to place or direct the placement of bait
. . . .”).
     4
      The Fourth Circuit reached a different conclusion in an unpublished
per curiam opinion in United States v. Cathey, 619 F. App’x 207, 210–11
(4th Cir. 2015) (per curiam). In Cathey, the court affirmed a conviction
for unlawful baiting where the trial involved questions about whether the
defendant’s farming activities fell within the scope of § 20.21(i)(1).
Cathey, 619 F. App’x at 210–12. But Cathey does not analyze the
                 UNITED STATES V. OBENDORF                          17

Consequently, we conclude that § 20.21(i)(1) was not
relevant to the baiting charges Obendorf faced.

                                 III.

    The district court’s temporal requirement cropped up in
its jury instructions and in the evidentiary rulings that
prevented Obendorf from eliciting opinions about his
farming practices when he cross-examined the three State
Extension Specialists who testified at trial. The government
argues any error was harmless because § 20.21(i)(1) does not
apply to the baiting charges at issue in this case. We agree
that any error in the jury instructions was harmless. The
evidentiary rulings present a closer question.

    The jury instructions saddled the government with a
burden the law does not prescribe: to prove beyond a
reasonable doubt that the so-called Agricultural Practice
Exception did not apply. The instruction for the substantive
baiting charge, which the conspiracy charge cross-referenced,
stated:

            In Count Two, Mr. Obendorf is charged
        with Placing Bait for Migratory Game Birds,
        in violation of the Migratory Bird Treaty Act.
        In order for Mr. Obendorf to be guilty of this
        charge, the Government must prove each of
        the following elements beyond a reasonable
        doubt:



threshold question of whether § 20.21(i)(1) applies in unlawful baiting
cases. Insofar as Cathey represents the Fourth Circuit’s considered
judgment on the issue, we reach a different conclusion.
18             UNITED STATES V. OBENDORF

           1. That on or about November 2013, Mr.
           Obendorf placed or directed the placement
           of bait on or adjacent to an area;

           2. Mr. Obendorf did so for the purpose of
           causing, inducing, or allowing any person
           to take or attempt to take any migratory
           game bird by the aid of baiting on or over
           a baited area; and

           3. The Agricultural Practice Exception
           does not apply.

           If the Government fails to prove any one
       of these elements beyond a reasonable doubt,
       your verdict on this Count must be Not
       Guilty.

This instruction tasked the government with disproving an
exception that did not apply in the first place. Consequently,
we conclude that any error in the jury instructions was
harmless beyond a reasonable doubt. See United States v.
Pheaster, 544 F.2d 353, 362 n.3 (9th Cir. 1976) (finding
harmless error where “[t]he instructions placed a heavier
burden on the government than was proper” and “the
defendants were convicted under [the] heavier standard”).

    The district court’s evidentiary rulings are thornier.
Obendorf was not allowed to cross-examine the three State
Extension Specialists who testified at trial about whether his
farming practices comported with their official
recommendations. In one sense, any error on this score was
harmless because no so-called Agricultural Practice
Exception was available to Obendorf. But Obendorf argues
               UNITED STATES V. OBENDORF                     19

that he was disadvantaged because he was prevented from
eliciting testimony that may have helped show he lacked the
requisite intent to bait the duck field. He also argues that he
was prejudiced because the government effectively invited
him to construct a defense theory around a regulatory safe
harbor that it now maintains does not apply. We are leery of
the government’s shift in position and note that its legal error
surely added to the expense, effort, and time required to
litigate this case. Nevertheless, our review of the record
convinces us that this error did not affect the verdict. United
States v. Decoud, 456 F.3d 996, 1010 (9th Cir. 2006).

    To convict Obendorf of illegal baiting, the government
had to prove beyond a reasonable doubt: (1) that Obendorf
baited the duck field, or ordered others to bait the duck field;
and (2) that he did so in order to facilitate hunting aided by
bait. See 16 U.S.C. § 704(b)(2). The evidence establishing
both these elements was extremely strong.

    First, the jury heard from multiple witnesses that
Obendorf directed his employees to bait the duck field.
Andrew Deboer, a former Obendorf farmhand, testified that
Obendorf told him to configure the combine harvester used
on the duck field so that it would spill corn kernels onto the
ground to “leave behind the maximum amount of corn for the
ducks.” According to Deboer, this directive was unique to
the duck field: when he harvested other cornfields on
Obendorf’s property, he had to readjust the combine’s
settings and regularly check to ensure that he was not “losing
too much grain.” Another former employee, Herb Troyer,
gave similar testimony. Troyer told the jury that he worked
for Obendorf and his sons for five years, including a stint as
a combine operator. Like Deboer, Troyer testified that he
was supposed to harvest most of Obendorf’s cornfields as
20              UNITED STATES V. OBENDORF

completely as possible, but he received special instructions
from Obendorf about the duck field. For it, Troyer was told
to “open the combine up[,] . . . spilling everything out the
back.”

    The jury also heard from Josh Kling, an experienced duck
hunter who worked as a mechanic on Obendorf’s farm for
several years but had since fallen out with Obendorf. Kling
testified that he consulted with Obendorf about how to best
manage the property for duck hunting, and that he and
Obendorf discussed strip combining the duck field but not
Obendorf’s other cornfields. Kling told the jury that he and
Obendorf discussed harvesting the duck field by “clos[ing] up
the combine to kind of let a bunch of the corn blow out the
back of it . . . [t]o leave it on the ground for the ducks, to feed
the ducks.”

    Ample evidence also established that Obendorf’s scheme
was designed to lure ducks for hunting. For example, Kling
testified that when “hunting [in the duck field] got bad,”
Obendorf directed him to knock down still-standing corn,
under the guise of creating a “windstorm,” to feed the ducks.
And Andrew Deboer testified that he knew he was illegally
baiting a field used for hunting, but that he did so because
Obendorf told him to. Obendorf’s son Brock also testified on
cross-examination that they strip-combined the duck field
“for hunting purposes.”

    On appeal, Obendorf stressed that he would have pursued
a different trial strategy if he had not been led to believe he
could find refuge in a regulatory safe harbor. At oral
argument, he indicated that, but for the government’s
erroneous representation that the Agricultural Practice
Exception was a potential defense, he would have devoted
               UNITED STATES V. OBENDORF                     21

more energy to undercutting the government’s proof on the
two actual elements of unlawful baiting. But our review of
the record reveals that Obendorf did just that, and the jury
was not persuaded.

    First, Obendorf introduced evidence that he was simply
farming and did not intend to bait the duck field for hunting.
He called his son and another employee to testify that they
strip-combined the duck field so that their cattle could eat the
unharvested corn in the spring. Obendorf also called a local
farmer who testified that Obendorf’s farming practices were
not out of the ordinary, and that some spillage from a
combine is inevitable.

    Second, Obendorf sought to undermine the credibility of
the government’s witnesses. On cross-examination, he asked
government witnesses about prior convictions, past game
violations, and unsavory personal remarks. One government
witness admitted that employees from the Idaho Department
of Fish and Game occasionally hunted the duck field. And in
his case-in-chief, Obendorf elicited testimony from one of his
employees that investigators threatened the employee into
cooperating. Perhaps most importantly, the jury heard that
Obendorf and Josh Kling—a key government witness who
provided the initial tip that Obendorf was baiting
ducks—were in a “full-blown feud” at the time of trial, and
that Kling cooperated with investigators out of animosity
towards Obendorf.

    Finally, the district court did not prevent Obendorf from
challenging the government’s evidence regarding his intent.
The district court explained that Obendorf could, in his case-
in-chief, “introduce evidence from a farmer or farm expert”
that his practices “had legitimate farming purposes other than
22              UNITED STATES V. OBENDORF

baiting a field for hunters,” to rebut the government’s proof
that he intended to lure ducks for hunting. The district court
explained that such testimony was not categorically
precluded, but that it would not be allowed on cross-
examination of witnesses who “were called simply to discuss
the regulatory Agricultural Practice Exception” because it
went beyond the scope of the direct examination. Nothing in
the district court’s ruling prevented Obendorf from calling the
same three State Extension Specialists during his case-in-
chief and asking them to opine on his farming practices. In
fact, the district court concluded, “this ruling does not block
the defense from putting on evidence during their case
regarding the ‘purpose’ element that the Government must
prove.”

                           *    *    *

    In the end, we cannot see what Obendorf would have
done differently if the parties had not misapprehended the
MBTA regulations. In a trial without the distraction of
§ 20.21(i)(1), the government would have had to prove:
(1) that Obendorf baited the duck field, or ordered others to
bait the duck field; and (2) that he did so in order to facilitate
hunting aided by bait. See 16 U.S.C. § 704(b)(2). The
evidence establishing those elements was extremely strong,
even in the face of Obendorf’s attempts to undercut the
government’s proof. Moreover, the jury instructions treated
the two actual elements of unlawful baiting as wholly discrete
from the so-called Agricultural Practice Exception,
ameliorating any potential for confusion. In the face of
overwhelming evidence establishing that Obendorf baited the
duck field in order to facilitate duck hunting, we conclude
that the erroneous application of § 20.21(i)(1) did not affect
the verdict. See Decoud, 456 F.3d at 1010.
              UNITED STATES V. OBENDORF                 23

                       Conclusion

    The Migratory Bird Treaty Act regulations do not create
a regulatory exception to the MBTA’s ban on unlawful
baiting. Obendorf was charged with unlawful baiting, not
unlawful hunting, so 50 C.F.R. § 20.21(i)(1) could not have
immunized his conduct.            Although the parties
misapprehended the law below, any error was harmless.
Accordingly, Obendorf’s conviction is AFFIRMED.
