                            PUBLISHED

UNITED STATES COURT OF APPEALS
                FOR THE FOURTH CIRCUIT


UNITED STATES OF AMERICA,              
                 Plaintiff-Appellee,
                 v.                               No. 01-4857
JAMES EVERETTE WORRELL,
              Defendant-Appellant.
                                       
           Appeal from the United States District Court
   for the Eastern District of North Carolina, at Elizabeth City.
             Terrence W. Boyle, Chief District Judge.
                          (CR-00-11-BO)

                      Argued: September 25, 2002

                      Decided: December 17, 2002

                 Before TRAXLER, Circuit Judge,
              HAMILTON, Senior Circuit Judge, and
      Claude M. HILTON, Chief United States District Judge
     for the Eastern District of Virginia, sitting by designation.



Affirmed by published opinion. Judge Traxler wrote the opinion, in
which Senior Judge Hamilton and Chief Judge Hilton joined.


                             COUNSEL

ARGUED: George Alan DuBois, Assistant Federal Public Defender,
Raleigh, North Carolina, for Appellant. Dennis M. Duffy, Assistant
United States Attorney, Raleigh, North Carolina, for Appellee. ON
BRIEF: Thomas P. McNamara, Federal Public Defender, Raleigh,
2                     UNITED STATES v. WORRELL
North Carolina, for Appellant. John Stuart Bruce, United States Attor-
ney, Anne M. Hayes, Assistant United States Attorney, Raleigh,
North Carolina, for Appellee.


                              OPINION

TRAXLER, Circuit Judge:

   James Worrell was convicted by a jury on two counts of mailing
threatening communications. See 18 U.S.C.A. § 876 (West 2000). He
received a prison sentence of 115 months. On appeal, Worrell con-
tends that the district court erroneously excluded expert testimony
regarding how his unmedicated mental condition affected his behav-
ior at the time the threatening letters were mailed. Worrell also chal-
lenges his sentence, arguing that the district court improperly applied
a six-level sentencing enhancement based on its determination that
"the offense involved . . . conduct evidencing an intent to carry out"
the threats contained in the letters. U.S. Sentencing Guidelines Man-
ual (U.S.S.G.) § 2A6.1(b)(1) (2000). We reject these arguments and
affirm Worrell’s convictions and his sentence.

                                   I.

    Worrell was incarcerated for an unrelated crime when he became
convinced that Theresa Roberson, his former girlfriend and the
mother of two of his children, had become romantically involved with
another man. Worrell, who was due to be released from prison in late
2000, admits writing and mailing from prison a series of threatening
letters to Theresa. Federal law makes it a crime to "knowingly depos-
it[ ] in any post office or authorized depository for mail matter, to be
sent or delivered by the Postal Service" or to "knowingly cause[ ]" the
Postal Service to deliver "any communication with or without a name
or designating mark subscribed thereto, addressed to any other person
and containing any threat to . . . injure the person of the addressee or
of another." 18 U.S.C.A. § 876.

  In one of the letters, dated February 28, 2000, Worrell wrote to
Theresa that he knew she was "seeing some guy that [she] work[ed]
                      UNITED STATES v. WORRELL                         3
with" and that he intended to "[p]ut a stop to it." J.A. 445. Worrell
warned that "[w]hoever this guy is better be watching his ass
[b]ecause I intend to do some harm . . . [a]nd I will be loaded for bear.
If you know what I mean." J.A. 445-46. Worrell also boasted that he
could have someone hurt the man while Worrell was still incarcer-
ated, but explained that he preferred to "do it [himself]. It’ll be a lot
more fun that way. . . . [H]e is a dead man if I catch him." J.A. 446-
47. Before closing the letter, Worrell switched his attention to There-
sa’s stepfather, Mike, threatening that "this time I will get Mike. The
first time you stopped me. This time you won’t." J.A. 446. Theresa
testified that she was attracted to a man with whom she worked but
denied that they were romantically involved. Theresa also testified
that Worrell and Mike had gotten into arguments about Worrell’s
physically abusive treatment of Theresa. Similarly, Worrell testified
that he and Mike never got along and came close to blows but were
restrained by other people. This letter was the basis for count one of
the indictment.

   Shortly after sending the February 28 letter, Worrell began threat-
ening Theresa. In a letter dated March 20, 2000, Worrell opened with
an obscenity-laced tirade against Theresa and her mother and closed
with the following threat: "No matter what the law says I can always
get a gun and no one can stop what I plan on doing with it. Can you
guess what I plan on doing? Bang-Bang Bitch. Ha-Ha. How do you
like that. . . . [Y]ou have been a very bad girl. So you mu[st] pay with
your life." J.A. 451-52. The threats contained in the March 20 letter
served as the basis for count two of the indictment.

   Worrell’s initial strategy was to raise a defense based on his diag-
nosis of bipolar disorder and intermittent explosive disorder. Prior to
trial, Worrell moved for permission to file an untimely notice of an
insanity defense under Rule 12.2(a) of the Federal Rules of Criminal
Procedure, which the district court granted. Worrell also filed a notice
pursuant to Rule 12.2(b) that he intended to present "expert testimony
relating to [Worrell’s] mental condition bearing on the issue of his
guilt" from Dr. George Corvin, a forensic psychiatrist. J.A. 17.

   After interviewing Worrell for approximately an hour and review-
ing Worrell’s mental health records, Dr. Corvin summarized his con-
clusions in a letter to Worrell’s attorney which was proffered to the
4                      UNITED STATES v. WORRELL
district court as reflecting the substance of Dr. Corvin’s expected testi-
mony.1 Dr. Corvin noted that the diagnoses of bipolar affective disor-
der and intermittent explosive disorder were "well supported by
information obtained" during his evaluation of Worrell, and that Wor-
rell "responded well to treatment with mood stabilizing and antipsy-
chotic medications." J.A. 48. However, Dr. Corvin reported that when
Worrell is not treated, "he experiences extreme affective instability,
mood swings, irritability, grandiosity, impaired judgment, and disor-
ganized thinking." J.A. 48. Observing that the medical staff at the
Roanoke City Jail had discontinued Worrell’s medication on February
16, 2000, shortly before he sent the first in his series of letters to The-
resa, Dr. Corvin opined that "[a]lthough there is no clear indication
that Mr. Worrell’s psychiatric symptoms . . . around the time of his
alleged offense were of sufficient severity to totally negate his ability
to understand the nature[,] quality[,] or wrongfulness of his actions,
it is quite clear that he was quite impaired psychiatrically during the
time in question." J.A. 49. Dr. Corvin concluded that Worrell’s "un-
treated psychiatric illness contributed substantially to the commission
of his alleged offenses" and "the fact that he was taken off his medica-
tion clearly played a critical role in the gradual psychiatric decompen-
sation that took place in the days leading up to his alleged offenses."
J.A. 49. Dr. Corvin’s letter did not address Worrell’s intent to mail
the letters to Theresa.

   After receiving Dr. Corvin’s summary of his evaluation of Worrell,
the government moved in limine to exclude any evidence relating to
Worrell’s mental condition.2 The government made a two-fold argu-
ment based on the federal insanity defense, see 18 U.S.C.A. § 17(a)
    1
     Worrell did not make a formal proffer of Dr. Corvin’s proposed testi-
mony either at the pre-trial hearing or at trial.
   2
     The government also filed a motion requesting that Worrell be
required to submit to a mental examination. The district court granted the
motion and referred Worrell to Dr. Mark Brooks, a forensic psychologist.
After interviewing Worrell and reviewing his mental health records, Dr.
Brooks concluded that "although the defendant may have experienced
symptoms of mental disorder at the time of the offenses charged, the
defendant possessed the clear intention to threaten the recipient of the
letters and the clear intention that the letter was to be delivered to the
recipient through the U.S. mail." J.A. 88.
                       UNITED STATES v. WORRELL                         5
(West 2000), which was enacted through the Insanity Defense Reform
Act ("IDRA"), Pub. L. No. 98-473, Title II, § 402(a), 98 Stat. 2057
§ 20 (1984). First, the government contended that IDRA absolutely
precludes a federal defendant from presenting any evidence relating
to defendant’s mental condition unless the defendant is pursuing a
formal affirmative insanity defense. Second, the government argued
that even if IDRA allows a defendant to offer such evidence, it would
be for the narrow purpose of negating a specific intent element of a
crime, and Dr. Corvin’s opinion, as summarized in his letter to
defense counsel, did not offer a basis to negate the specific intent
required for the offense of mailing a threatening communication
under § 876.

   Given that Dr. Corvin could not say that Worrell was unable to
appreciate the nature and quality or wrongfulness of his criminal acts,
counsel for Worrell candidly conceded to the district court that Wor-
rell did not qualify for an insanity defense. However, Worrell still
sought to introduce Dr. Corvin’s testimony on the basis that mailing
a threatening communication in violation of § 876 is a specific intent
crime, and that Dr. Corvin’s testimony would negate the specific
intent that the government was required to prove for a conviction
under § 876.

   The district court granted the government’s motion to exclude Dr.
Corvin’s testimony. However, the district court did not prohibit Wor-
rell, who testified in his own defense, from telling the jury that he suf-
fered from "bipolar disorder and inter[mittent] explosive disorder,"
J.A. 254, that when he does not take his medication, he does not "re-
ally think about what [he is] doing before [he does] it," J.A. 255, and
that, prior to writing the first letter to Theresa, he had been taken off
of his medication. In fact, Worrell’s attorney emphasized this point
during his closing argument, suggesting to the jury that Worrell’s
"case would not be in front of you if it were not for the fact that, as
Mr. Worrell testified, that he was taken off of his medication" and
that "there were no letters submitted to you that were threatening
while he was on his medication." J.A. 298.

   On cross-examination, Worrell admitted writing the letters and
mailing them to Theresa. He acknowledged that he understood that a
letter must have an address and a zip code, that it requires a stamp and
6                      UNITED STATES v. WORRELL
that it is delivered by the Postal Service. Worrell’s testimony also
reflected his understanding of certain internal prison mail procedures.
Worrell explained that as an inmate, he was entitled to three free
stamps per week, and that he had already used his allotment when he
sent the February 28 letter to Theresa. Because he was out of stamps,
Worrell used a fellow inmate’s name for the return address in order
to obtain an extra stamp free of charge.

   Worrell further conceded that he had been trying to scare Theresa
with his letters, and one of the investigating agents testified that Wor-
rell told him the purpose of the letters was to threaten Theresa in
response to her apparent desire to obtain exclusive custody of his chil-
dren. Given the history of physical abuse and threats of violence
inflicted by Worrell, it probably would have been unreasonable for
Theresa simply to dismiss these threats as harmless. Theresa testified
that throughout her three-year relationship with Worrell, he regularly
beat her with his fists if she said or did something that angered him.
Theresa further testified that on one occasion, with the children pres-
ent, Worrell held a gun near her head and threatened to shoot her.
Although Worrell denied holding the gun close to her head, he admit-
ted that he pulled a gun on Theresa and pointed it towards her from
"about eight paces away." J.A. 273. He also admitted striking Theresa
with his hand during their relationship.

  The jury concluded that Worrell violated § 876 by mailing the Feb-
ruary 28 and March 20 letters and returned a guilty verdict on both
counts of the indictment. On appeal, Worrell challenges the district
court’s decision to exclude the evidence of his mental condition.

   Worrell also appeals his sentence. Adopting the recommendation
set forth in the presentence report, the district court applied a six-level
enhancement based on Worrell’s past abuse of Theresa, which the
court concluded to be conduct evidencing Worrell’s intent to carry out
his threats. The district court also departed upward by one level based
on its conclusion that Worrell’s criminal history score failed to
account for his extensive previous criminal activity. Worrell appeals
the six-level enhancement, but he does not challenge the upward
departure.
                      UNITED STATES v. WORRELL                       7
                                  II.

   Worrell argues that the district court committed reversible error
when it barred the introduction of Dr. Corvin’s testimony about the
effect of Worrell’s unmedicated bipolar and intermittent explosive
disorders at the time that Worrell wrote and mailed the letters to The-
resa. Worrell contends that he intended to present this expert testi-
mony to show that, "as a result of his impaired mental state, he did
not possess the specific intent necessary to commit" the offense of
conviction. Brief of Appellant at 14. Accordingly, he argues, IDRA
did not preclude the introduction of such testimony because he was
not pursuing an affirmative insanity defense.

                                  A.

  IDRA codified the federal standard for an insanity defense, and
provides as follows:

    (a) Affirmative defense.—It is an affirmative defense to a
    prosecution under any Federal statute that, at the time of the
    commission of the acts constituting the offense, the defen-
    dant, as a result of a severe mental disease or defect, was
    unable to appreciate the nature and quality or the wrongful-
    ness of his acts. Mental disease or defect does not otherwise
    constitute a defense.

    (b) Burden of proof.—The defendant has the burden of
    proving the defense of insanity by clear and convincing evi-
    dence.

18 U.S.C.A. § 17.

   Prior to the enactment of IDRA, we followed the test formulated
by the American Law Institute ("ALI") which provided, in part, that
"[a] person is not responsible for criminal conduct if at the time of
such conduct as a result of mental disease or defect he lacks substan-
tial capacity either to appreciate the criminality of his conduct or to
conform his conduct to the requirements of law." United States v.
Chandler, 393 F.2d 920, 926 (4th Cir. 1968) (en banc) (internal quo-
8                     UNITED STATES v. WORRELL
tation marks omitted) (emphasis added); see United States v. Gould,
741 F.2d 45, 47 (4th Cir. 1984) (explaining that "[t]he substantive
‘insanity defense’ rule in this circuit is the ALI test as adopted in
United States v. Chandler"). The latter part of this definition, there-
fore, afforded a defense premised on lack of volitional control. That
is, a defendant could escape criminal liability if he was able to prove
he lacked substantial capacity to control his actions, even though he
may have been aware of what he was doing and understood that his
actions were unlawful.

   In passing IDRA, Congress rejected the "volitional prong" of the
ALI test. See United States v. Cameron, 907 F.2d 1051, 1061 (11th
Cir. 1990); United States v. Pohlot, 827 F.2d 889, 896 (3rd Cir.
1987). IDRA expressly prohibits the use of any "[m]ental disease or
defect" as a defense unless it demonstrates that the defendant "was
unable to appreciate the nature and quality or the wrongfulness of his
acts." 18 U.S.C.A. § 17. The language of the statute leaves no room
for a defense that raises "any form of legal excuse based upon one’s
lack of volitional control" including "a diminished ability or failure
to reflect adequately upon the consequences or nature of one’s
actions." Cameron, 907 F.2d at 1061.

   Therefore, the government argued to the district court that IDRA
absolutely bars the introduction of evidence regarding mental disease
or defect unless the defendant is pursuing a formal affirmative insan-
ity defense. Worrell, however, contended that he was not introducing
evidence of his mental disorders to support an affirmative defense or
legal excuse, but rather to negate one of the elements of the govern-
ment’s case. Specifically, Worrell asserted that as a result of his bipo-
lar disorder and his intermittent explosive disorder, he did not possess
the specific intent to mail threatening communications in violation of
18 U.S.C.A. § 876.

   The district court did not specifically address the broad issue of
whether IDRA permits a defendant who is not pursuing an insanity
defense to use evidence of a mental disease or defect to negate spe-
cific intent. We note that, on appeal, the government has not vigor-
ously pursued its position on this particular issue. Indeed, the circuits
addressing this issue appear to agree that, despite IDRA, psychiatric
testimony regarding a defendant’s mental condition can still be used
                      UNITED STATES v. WORRELL                         9
in appropriate circumstances to disprove specific intent for specific
intent crimes. See Cameron, 907 F.2d at 1063-66; United States v.
Newman, 889 F.2d 88, 91-92 & n.1 (6th Cir. 1989); United States v.
Bartlett, 856 F.2d 1071, 1081-82 (8th Cir. 1988); United States v.
Twine, 853 F.2d 676, 678 79 (9th Cir. 1988); Pohlot, 827 F.2d at 897.
This conclusion rests on the distinction between psychiatric testimony
or evidence supporting an affirmative defense that "justif[ies] or
excuse[s] conduct that is otherwise criminal," and psychiatric evi-
dence that merely "aids the trier in determining the defendant’s spe-
cific state of mind with regard to the actions she took at the time the
charged offense was committed, . . . [which] is not an affirmative
defense but is evidence that goes specifically to whether the prosecu-
tion has carried its burden of proving each essential element of the
crime." Cameron, 907 F.2d at 1063 (internal quotation marks omit-
ted). These decisions interpret IDRA as barring psychiatric evidence
relating to a defendant’s mental condition — short of insanity — if
such evidence is in the nature of "a legal justification or excuse for
otherwise criminal conduct," but permitting this type of evidence if,
rather than justifying defendant’s conduct, it "negates an essential ele-
ment of the government’s prima facie case." Id. at 1065. An example
of inadmissible evidence regarding a defendant’s mental condition
would be testimony that a defendant, who failed to meet IDRA’s defi-
nition of insanity, committed a crime because of a "supposed psychi-
atric compulsion or inability or failure to engage in normal
reflection." Pohlot, 827 F.2d at 890.

   This distinction seems clear enough in theory, if not in practice.
We confess we have difficulty envisioning many scenarios in which
a defendant could introduce psychiatric evidence, short of insanity,
that was not simply diminished capacity evidence or some other form
of justification in disguise. See Cameron, 907 F.2d at 1066 ("When
a defendant claims to have psychiatric evidence that she ‘lacked the
capacity’ or was ‘incapable’ of forming the intent necessary for the
crime charged, most often that defendant is speaking of an incapacity
to reflect or control the behaviors that produced the criminal con-
duct."); Pohlot, 827 F.2d at 900 ("Only in the rare case . . . will even
a legally insane defendant actually lack the requisite mens rea purely
because of mental defect."). Both the Eleventh and Third Circuits,
which have considered this issue in depth, offer the same example of
10                     UNITED STATES v. WORRELL
an appropriate use of non-insanity psychiatric evidence to negate an
element of the government’s case:

      United States v. Staggs, 553 F.2d 1073 (7th Cir. 1977), pro-
      vides an example of the appropriate use of "psychiatric evi-
      dence to negate specific intent." Mr. Staggs was charged
      with threatening to shoot a policeman. He denied making
      the threat and sought to introduce psychiatric evidence that
      he suffered from a mental condition that made it highly
      unlikely that he would make such a threat. The Seventh Cir-
      cuit reversed the district court’s exclusion of this evidence
      since it did not imply a legal excuse for the conduct engaged
      in by Staggs, nor did it suggest a theory of unconscious
      motivation or lack of volitional control. The evidence
      instead shed light on whether Staggs possessed a specific
      state of mind that would make him guilty of a more serious
      crime than his conduct alone would support.3

Cameron, 907 F.2d at 1067; see Pohlot, 827 F.2d at 897. In other
words, Staggs was offering the psychiatric evidence to show he did
not do it, not that he could not help it.

   We are inclined to agree with those courts holding that IDRA does
not prohibit psychiatric evidence of a mental condition short of insan-
ity when such evidence is offered purely to rebut the government’s
evidence of specific intent, although such cases will be rare. In any
event, we need not plumb the depths of this issue to determine that
the district court properly excluded the testimony of Dr. Corvin.

                                   B.

   Assuming that IDRA permits psychiatric testimony to be presented
to negate the specific intent element of a specific intent crime, Dr.
Corvin’s proposed testimony is simply not relevant to the issue of
  3
   Staggs was overruled on grounds unrelated to this discussion. See
United States v. Ricketts, 146 F.3d 492, 497 (7th Cir. 1998) (explaining
that the Seventh Circuit no longer follows its conclusion in Staggs that
18 U.S.C.A. § 111 is a general intent crime).
                      UNITED STATES v. WORRELL                       11
specific intent in this case. Accordingly, the district court committed
no error in its decision to exclude his testimony.

   Worrell is correct that the offense of mailing a threatening commu-
nication under § 876 is a specific intent crime; however, that fact does
not aid him. Section 876 does not require specific intent to threaten;
rather, "[t]he only proof of specific intent required to support a con-
viction under . . . § 876 is that the defendant knowingly deposits a
threatening letter in the mails, not that he intended or was able to
carry out the threat." United States v. Chatman, 584 F.2d 1358, 1361
(4th Cir. 1978) (emphasis added). The proper focus is "on the act of
mailing, not on the act of threatening." United States v. Darby, 37
F.3d 1059, 1065 (4th Cir. 1994). The government is required to prove
only a general intent to threaten under § 876, see United States v.
Maxton, 940 F.2d 103, 106 (4th Cir. 1991), which means that the
communication must "encompass a ‘true threat,’" id.; see Darby, 37
F.3d at 1065. A "true threat" is determined not by the defendant’s
subjective mindset, but by the objective standard of whether a "rea-
sonable recipient who is familiar with the context of the letter would
interpret it as a threat of injury." Maxton, 940 F.2d at 106 (internal
quotation marks omitted).

   The brief synopsis of Dr. Corvin’s opinion appearing in the record,
which is all we have to go by since Worrell made no proffer, does not
address Worrell’s intent, or lack of intent, to deposit threatening com-
munications in the mails. Thus, Dr. Corvin’s proposed opinion on its
face provides no basis to negate the specific intent element the gov-
ernment must prove to secure a conviction under § 876. In fact, the
only evidence we have regarding Worrell’s specific intent to mail the
letters is Worrell’s own trial testimony, which establishes that Worrell
understood the prison mail process and even manipulated the system
to his advantage. Worrell acknowledged that he purposely placed the
letters in the mail with the realization that the Postal Service would
deliver them to the intended addressee.

  Because Dr. Corvin’s opinion, as summarized in his letter to
defense counsel, does not address Worrell’s intent to mail the letters
and therefore fails to negate the specific intent required under § 876,
we are left with precisely the kind of psychiatric evidence that IDRA
precludes. Dr. Corvin’s opinion was essentially that because Worrell
12                     UNITED STATES v. WORRELL
was not taking his medication at the time of the offenses, he was not
able to exercise control over his actions or reflect on the possible con-
sequences of his actions. Taking into account Worrell’s acknowledg-
ment that, when he is off of his medication, "I lose control, I try not
to, but I lose it. . . I know I’m being stupid, but I still can’t stop," J.A.
49, Dr. Corvin concluded that Worrell had the ability to understand
the nature and quality of his actions but that he was psychiatrically
impaired at the time of the offenses as indicated by his "impulsivity,
mood swings, extreme irritability, disorganized thinking, and
impaired judgment." J.A. 49. This evidence is clearly calculated to
show that Worrell, because of his unmedicated bipolar and intermit-
tent explosive disorders, was not able to control his behavior or reflect
on potential consequences before acting. This is no different than evi-
dence that Worrell lacked the ability to conform his behavior to the
requirements of law. IDRA bars a defendant who is not pursuing an
insanity defense from offering evidence of his lack of volitional con-
trol as an alternative defense. Accordingly, the district court properly
excluded this evidence.

                                    III.

   Worrell next contends that the district court erroneously applied a
six-level enhancement to his base offense level under the Sentencing
Guidelines. The guideline for Worrell’s offenses is contained in
§ 2A6.1 and, as is applicable to this case, sets a base offense level of
12 for threatening communications. See U.S.S.G. § 2A6.1(a)(1)
(2000). Section 2A6.1 provides further that "[i]f the offense involved
any conduct evidencing an intent to carry out such threat," the sen-
tencing court must "increase [the base offense level] by 6 levels."
U.S.S.G. § 2A6.1(b)(1).

   The presentence report ("PSR") submitted to the district court rec-
ommended that the court apply this six-level enhancement because of
Worrell’s history of violence in his relationship with Theresa. The
PSR referred generally to Worrell’s violent conduct directed at The-
resa and specifically identified two incidents in support of the recom-
mendation that the enhancement be applied. According to the PSR,
"[b]oth Ms. Roberson and Worrell have described situations in which
the defendant physically and mentally abused Ms. Roberson," includ-
ing one incident in which "Ms. Roberson was beaten so badly that her
                      UNITED STATES v. WORRELL                       13
eardrum was ruptured" and another in which "Worrell pointed a .25
caliber handgun at Roberson threatening to kill her," which led to
Worrell’s arrest and conviction. J.A. 499. And, as noted earlier, The-
resa recounted during trial similar incidents of violence she suffered
at the hands of Worrell over the course of their three-year relationship
from 1994 to 1997. According to Theresa, she and Worrell got into
disagreements a few times each week that would result in his striking
her if she "said something wrong or something he didn’t like." J.A.
198. Theresa also described the incident in which Worrell pointed a
handgun at her head and threatened to shoot her. The district court
concluded that the government had proven that Worrell had engaged
in conduct evidencing his intent to carry out his threats, and, over
Worrell’s objection, adopted the recommendation of the PSR and
applied the six-level enhancement pursuant to U.S.S.G.
§ 2A6.1(b)(1).

   On appeal, Worrell makes a two-fold argument. First, he argues
that the § 2A6.1(b)(1) enhancement does not apply to prior conduct
unless such conduct is part of the offense itself or constitutes "rele-
vant conduct," see U.S.S.G. § 1B1.3, and that conduct occurring years
before the letters were mailed, like that cited in the PSR and relied
upon by the government, does not qualify as either. Second, Worrell
contends that even if such prior conduct could be considered under
U.S.S.G. § 2A6.1(b)(1), the conduct in this case was simply not suffi-
ciently connected to the offense. We address each of these arguments
in turn.

                                  A.

   Worrell first argues that conduct occurring prior to the mailing of
a threatening communication which is not part of the offense itself
cannot be used to apply the six-level enhancement because, for the
enhancement to apply, the guidelines require that "the offense
involve[ ] . . . conduct evidencing an intent to carry out such threat."
U.S.S.G. § 2A6.1(b)(1) (emphasis added). Worrell argues that the text
of the guideline mandates that any conduct used as the basis for
applying the enhancement under § 2A6.1(b)(1) must either be part of
the offense itself or must qualify as "relevant conduct" under § 1B1.3
of the Sentencing Guidelines. In support of this contention, Worrell
cites the commentary on the Guideline’s "Application Instructions."
14                    UNITED STATES v. WORRELL
See U.S.S.G. § 1B1.1. The commentary provides a definition of "gen-
eral applicability" for the term "offense": "‘Offense’ means the
offense of conviction and all relevant conduct under § 1B1.3 (Rele-
vant Conduct) unless a different meaning is specified or is otherwise
clear from the context." U.S.S.G. § 1B1.1, comment. (n.1(l)). Worrell
suggests that his history of physically abusing Theresa occurred years
before he mailed the threatening letters and is obviously not part of
the offense. And, given that the government does not suggest that
Worrell’s prior acts constitute "relevant conduct," Worrell concludes
that his past abuse of and threats against Theresa cannot be used to
support the six-level enhancement.

   Under a previous version of the Sentencing Guidelines, we held
that prior conduct could properly be considered when determining
whether the defendant engaged in conduct revealing an intent to fol-
low through on the threats, justifying the application of the six-level
enhancement. See United States v. Gary, 18 F.3d 1123, 1128 (4th Cir.
1994). Under the 1992 version of the Sentencing Guidelines, which
applied in Gary, the six-level enhancement was appropriate "[i]f the
defendant engaged in any conduct evidencing an intent to carry out
such threat," U.S.S.G. § 2A6.1(b)(1) (1992) (emphasis added), as
opposed to the current version, which asks whether "the offense
involved any conduct evidencing an intent to carry out such threat,"
U.S.S.G. § 2A6.1(b)(1) (2000) (emphasis added). In Gary, we
reviewed a sentence imposed in 1992 and held that "[a]ny acts that
evidence an intent to carry out the threats on which a conviction is
predicated, whether committed prior to or following such threats, may
form the basis of the § 2A6.1(b)(1) adjustment." Gary, 18 F.3d at
1128. "[T]he pivotal inquiry is into the defendant’s intent and the
likelihood that the defendant would carry out the threat." Id. at 1127-
28 (internal quotation marks omitted). Gary affirmed the application
of the six-level enhancement based on threatening phone calls and
visits to the victim that were not part of the offense under § 876 and
that began more than six months before the offense conduct occurred.
See id. at 1127-28.

   In 1993, the Sentencing Commission amended § 2A6.1(b)(1) by
deleting the phrase "[if] the defendant engaged" and instead providing
that the enhancement applied if "the offense involved any conduct
evidencing an intent to carry out such threat." U.S.S.G. § 2A6.1;
                      UNITED STATES v. WORRELL                         15
U.S.S.G. App. C, amend. 480 (1993). Worrell suggests that the
amendment to § 2A6.1(b)(1) narrowed the scope of the enhancement
to the extent that it no longer applies to conduct that occurred prior
to the offense of mailing threatening communications.

   We disagree. First, Amendment 480 was intended to broaden the
scope of section 2A6.1(b)(1) by "delet[ing] language that could be
construed as a limitation on the scope of conduct for which a defen-
dant is accountable under § 1B1.3 (Relevant Conduct)." U.S.S.G.
App. C, amend. 480 (1993). Amendment 480 "responded to the possi-
bility that the previous language precluded consideration of any con-
duct of others for which a defendant was responsible under § 1B1.3,"
because the previous language focused on whether the defendant’s
conduct provided a basis for the enhancement. United States v.
Thomas, 155 F.3d 833, 838 (7th Cir. 1998) (internal quotation marks
omitted). Because Amendment 480 "made clear that a district court
could consider the conduct of others for which the defendant is
accountable under § 1B1.3," thereby effectively broadening the scope
of § 2A6.1(b)(1), we agree with the Seventh Circuit that the amend-
ment did not also "simultaneously limit the scope of the district
court’s inquiry to only relevant conduct." Id. at 839.

   Second, the Sentencing Commission added commentary in 1997,
almost four years before Worrell was sentenced in 2001, clarifying
that prior conduct, even if it does not constitute "relevant conduct,"
may provide the basis for a six-level enhancement under
§ 2A6.1(b)(1) as long as there is a substantial and direct connection
with the offense of conviction:

    In determining whether subsection[ ] (b)(1) . . . appl[ies], the
    court shall consider both conduct that occurred prior to the
    offense and conduct that occurred during the offense; how-
    ever, conduct that occurred prior to the offense must be sub-
    stantially and directly connected to the offense, under the
    facts of the case taken as a whole.

U.S.S.G. § 2A6.1, comment. note 2.

  The Sentencing Commission explained that the addition of this
commentary was intended to clear up a circuit split over "whether or
16                     UNITED STATES v. WORRELL
not conduct which occurred prior to the making of the threat can evi-
dence an intent to carry out the [subsequent] threat." U.S.S.G., App.
C, amend. 549 (1997). It is significant that in determining that pre-
threat conduct may be used if there is a substantial and direct connec-
tion with the offense, the Sentencing Commission cited and relied
upon Gary, among other decisions. See id. As mentioned before, Gary
applied the six-level enhancement based on threatening conduct that
occurred before the defendant violated § 876 by sending the threaten-
ing letters, and the prior conduct in Gary clearly was not part of the
offense and did not constitute relevant conduct.

   "[C]ommentary in the Guidelines Manual that interprets or explains
a guideline is authoritative unless it . . . is inconsistent with, or a
plainly erroneous reading of, that guideline." Stinson v. United States,
508 U.S. 36, 38 (1993). Perceiving no such inconsistency here, we
conclude that Application Note 2 to § 2A6.1(b)(1) clarifies the mean-
ing of the guideline and permits a district court to use prior conduct
for purposes of the six-level enhancement as long as the prior conduct
is "substantially and directly connected" to the offense.4 See Thomas,
155 F.3d at 838 (concluding that Amendment 549 "makes clear that
§ 2A6.1(b)(1) is not limited solely to relevant conduct, since the sen-
tencing judge may consider all prior conduct that is substantially and
directly related to the threatening communication.").

                                   B.

   We now consider the remaining issue of whether Worrell’s past
abuse and threats to Theresa are sufficiently connected with his
offense conduct to warrant the six-level enhancement for conduct evi-
dencing the intent to carry out the threats in his letters. We review de
novo a district court’s application of the Sentencing Guidelines to a
given factual scenario. See United States v. Franks, 183 F.3d 335, 337
(4th Cir. 1999). We believe that the connection between Worrell’s
prior abusive and threatening conduct towards Theresa and the letters
  4
   Worrell does not develop the argument that the commentary to
§ 2A6.1(b)(1) is, on its face, at odds with the guideline itself. Although
Worrell notes in his brief a potential conflict between the two, he con-
cludes that any such conflict is "more apparent than real." Brief of
Appellant at 31.
                       UNITED STATES v. WORRELL                         17
forming the basis for his convictions is sufficiently direct and substan-
tial. Evidence of past violence and abuse inflicted upon the victim by
the defendant, particularly when the threats refer to specific instances
of such conduct, may demonstrate that the defendant is not merely
blowing smoke but in fact is likely to follow through on his threats
and, therefore, provides a basis for an enhancement under
§ 2A6.1(b)(1). See United States v. Carter, 111 F.3d 509, 513-14 (7th
Cir. 1997) (applying the six-level enhancement under § 2A6.1(b)(1)
based partially on defendant’s frequent use of force against the victim
during their prior relationship); United States v. Sullivan, 75 F.3d 297,
302 (7th Cir. 1996) (concluding enhancement under § 2A6.1(b)(1)
was appropriate when the defendant sent a threatening letter that spe-
cifically referred to an incident in which the defendant had shot out
the windows in the victim’s truck three months earlier, thus "t[ying]
the prior acts to the threats . . . [and] implicating 2A6.1" (internal quo-
tation marks omitted)).

    First, the threats Worrell made in his letters were clearly connected
to the specifics of his prior acts of violence involving Theresa and
therefore plainly conveyed his intent to carry them out. For example,
in his March 20 letter, Worrell wrote, "No matter what the law says
I can always get a gun and no one can stop what I plan on doing with
it. Can you guess what I plan on doing? Bang-Bang Bitch. . . . you
mu[st] pay with your life." J.A. 451-52. Worrell’s selection of a gun
as his weapon of choice was no accident, as his reference to it was
obviously designed to remind Theresa of the time he had held a gun
to her head and threatened to shoot her. Similarly, in his February 28
letter to Theresa, Worrell stated, "I intend to do some harm . . . and
I will be loaded for bear. If you know what I mean." J.A. 445-46.
Again, Worrell harkens Theresa back to the acts of violence she had
personally witnessed, as a reminder to her of his ability and intent to
inflict the harm he promises.

   Significantly, Worrell’s specific references to prior violent epi-
sodes were made against a backdrop of testimony showing that There-
sa’s involvement with Worrell was essentially a three-year continuum
of threatened violence and physical abuse that proceeded on a weekly
basis until Worrell was sent to prison. Accordingly, it does not take
a great leap of logic to conclude that Worrell’s abuse of Theresa
would have continued but for the fact that he was incarcerated. In
18                    UNITED STATES v. WORRELL
other words, when Worrell wanted to strike her, he did. Worrell’s his-
tory of violence against Theresa which continued unabated during
their relationship clearly sheds light on Worrell’s intent to carry out
his threats, and Worrell’s specific reference to a few of these incidents
clearly links his past conduct with the fresh threats of harm contained
in the letters. We do not find it difficult to conclude that Worrell’s
past conduct in this case is directly and substantially related to his
offense.

   Lest there be any doubt about Worrell’s intent to draw on There-
sa’s past experiences with him to convey that his threats are real,
Worrell also referred expressly in his February 28 letter to unfinished
business with Theresa’s stepfather, Mike, warning that "[t]his time, I
will get Mike. The first time you stopped me. This time you won’t."
J.A. 446.

   In short, the prior acts, though occurring some period of time
before Worrell mailed the letters at issue, provided context for the
threats contained in the letters, giving enhanced meaning to the lan-
guage chosen and validity to the threats in general. By directly and
indirectly referencing past episodes, Worrell was reminding Theresa
that he had inflicted harm in the past and effectively demonstrating
that he would do so again. Consequently, we conclude the prior acts
were substantially and directly connected to the threats in the letters
to show Worrell’s intent to carry them out and that the district court
was correct to apply the six-level enhancement.

                                  IV.

   For the foregoing reasons, we affirm Worrell’s conviction and sen-
tence.

                                                            AFFIRMED
