                           PUBLISHED

UNITED STATES COURT OF APPEALS
                FOR THE FOURTH CIRCUIT


UNITED STATES OF AMERICA,               
                 Plaintiff-Appellee,
                 v.                             No. 04-4388
JAMES SCOTT ROBINSON,
              Defendant-Appellant.
                                        
UNITED STATES OF AMERICA,               
                 Plaintiff-Appellant,
                 v.                             No. 04-4417
JAMES SCOTT ROBINSON,
               Defendant-Appellee.
                                        
           Appeals from the United States District Court
       for the Eastern District of North Carolina, at Raleigh.
                Malcolm J. Howard, District Judge.
                           (CR-02-80-H)

                      Argued: March 17, 2005

                      Decided: April 18, 2005

     Before WILLIAMS, MOTZ, and SHEDD, Circuit Judges.



Affirmed in part, reversed in part, and remanded by published opin-
ion. Judge Williams wrote the opinion, in which Judge Motz and
Judge Shedd joined.
2                    UNITED STATES v. ROBINSON
                             COUNSEL

ARGUED: James M. Ayers, II, New Bern, North Carolina, for James
Scott Robinson. Felice McConnell Corpening, Assistant United States
Attorney, OFFICE OF THE UNITED STATES ATTORNEY,
Raleigh, North Carolina, for the United States. ON BRIEF: Frank D.
Whitney, United States Attorney, Anne M. Hayes, Assistant United
States Attorney, Raleigh, North Carolina, for the United States.


                             OPINION

WILLIAMS, Circuit Judge:

   James Scott Robinson, a juvenile tried as an adult, appeals his con-
viction and sentence for engaging in a string of armed robberies tar-
geting grocery stores and banks. The Government has cross-appealed,
asserting that the district court erred by sentencing Robinson to 384
months imprisonment. For the following reasons, we affirm Robin-
son’s conviction but remand the case to the district court for resen-
tencing.

                                  I.

   Robinson was born on December 27, 1984. In his early childhood,
he was abused by his mother, who was convicted of felony child
abuse when Robinson was three years old. Following his seventh
birthday, Robinson and his younger sister moved in permanently with
his paternal grandmother, Rosalie Crisp, who attempted to give Rob-
inson a stable home environment. Robinson has not seen his mother
since that time, and Robinson’s father has been incarcerated since
approximately that same time. Robinson had trouble in school, and
his I.Q. scores were generally below average, ranging from 74 to 90.
Robinson was placed on juvenile probation in April 2001 for possess-
ing 6.6 grams of marijuana in school. At that time, Robinson was in
the eighth grade. Robinson was expelled from school for that offense
and transferred to a school for students with special needs or behav-
ioral problems, but he was frequently suspended from the school for
aggressive behavior. In 2000, at the age of fifteen, Robinson began
                     UNITED STATES v. ROBINSON                       3
committing robberies with a friend, Anthony Sanders. Sanders was
twenty-four years old at the time. Sanders and Robinson committed
their first robbery on October 28, 2000, robbing a Food Lion in Clay-
ton, North Carolina. After Robinson indicated that he needed some
money, Sanders suggested they rob something. Wearing ski-masks
and carrying handguns, they went to the store’s office and demanded
money; they received approximately $3,000 in cash and $3,000 in
checks.

   The next robbery occurred on December 20, 2000 at a Piggly Wig-
gly store in Smithfield, North Carolina. On this occasion, Robinson
robbed the store by himself, and Sanders picked him up from Robin-
son’s half-sister’s house after the robbery. While Robinson was carry-
ing out this robbery, a man wearing a Santa Claus suit tried to
apprehend him, and Robinson fired his gun into the air inside the
store to scare him away. Robinson obtained about $800 from this rob-
bery.

   Next, on December 27, 2000, Sanders, Robinson, and another
friend, Kenny Horne, robbed the Four Oaks Bank in Smithfield,
North Carolina. Robinson again committed the actual robbery by him-
self and hid at Horne’s cousin’s house until Sanders and Horne could
come for him. During the robbery, Robinson wore a ski mask and car-
ried a handgun. Robinson approached the teller, demanded money,
and ultimately cocked the gun and threatened to kill her if she did not
give him the money. Robinson then obtained money from a second
teller’s till as well. Robinson netted $16,000 from this robbery.

   On January 10, 2001, Robinson, Horne, and Sanders went to rob
a Food Lion in Wilson, North Carolina. Sanders went in the store to
survey it and then exited. Robinson, wearing a dress belonging to
Sanders’ wife over his clothes and a ski mask, entered the store armed
with a handgun and demanded to be let into the office. Robinson also
demanded money from the safe, but it was closed and could not be
opened. During this time, Robinson had his gun pointed at the store
employee’s head. Robinson left the store with $2,000. Believing that
he was being followed by the police, he jumped a fence, disposed of
the dress, gun, and money, hid for a while, and then strolled through
a housing development.
4                    UNITED STATES v. ROBINSON
   While walking through the development, Robinson was stopped by
a Wilson police officer. The officer asked Robinson his name and
address; Robinson responded that his name was "Junior Crisp," and
he gave his grandmother’s address as his own. Robinson had scuff
marks on his hands and a hole in his jeans. Robinson told the officer
he was searching for a relative who lived somewhere in the develop-
ment. Robinson agreed to accompany the officer to the Food Lion for
a "show up," but none of the employees identified him. After the offi-
cer released Robinson near the development, Sanders and Horne
found him. The three men then drove to a nearby home where Robin-
son recovered the items he had left.

   After further investigation, Wilson Police Detective Bass obtained
an arrest warrant for Robinson. Bass served the warrant on January
12, 2001 at Crisp’s home. Detective Bass read Robinson the warnings
required by Miranda v. Arizona, 384 U.S. 436, 467-73 (1966),1 and
Robinson indicated he understood those warnings. Robinson and his
grandmother both signed a form indicating that the Miranda warnings
had been read to him. Robinson was taken to the Wilson County Jail
where he was questioned. Robinson denied his involvement in the
robbery at that time.

   On January 30, 2001, Robinson was visited in jail by Sergeant
Martin, of the Smithfield Police Department, who wanted to question
Robinson regarding the Four Oaks Bank and Piggly Wiggly rob-
beries. Martin advised Robinson of his juvenile Miranda rights, and
Robinson signed a waiver of rights form. At no point did Robinson
indicate that he did not understand those rights. Robinson again
denied his involvement in any robbery at that time.

   After being released, Robinson continued his spree. On May 25,
2001, Robinson told Horne, Sanders, and Travis Groves, Sanders’s
younger brother, that he needed a ride so he could commit a robbery.
The four individuals traveled to Smithfield, North Carolina, where
they decided to rob the Food Lion. Robinson again committed the
    1
   Bass actually read Robinson rights from a juvenile Miranda form,
which specified that, in addition to the rights guaranteed by Miranda,
Robinson had the right to request the presence of a parent or guardian
during questioning.
                     UNITED STATES v. ROBINSON                       5
crime, wearing a mask over his face and entering the store carrying
a handgun. As Robinson fled around back of the store where Sanders,
Groves, and Horne were waiting in the getaway car, a store employee
gave chase. Robinson turned, aimed the gun at the employee, and
fired it at him. The four men then escaped with approximately $1,200.

   On June 1, 2001, Robinson told Sanders, Horne, and Groves that
he had discovered a bank they could rob. Sanders, Groves, and Robin-
son drove to Garner, North Carolina, to survey the bank in question.
After deciding where to pick up Robinson after the robbery, Sanders
and Groves dropped Robinson off near the bank. Robinson entered
the Dixie Construction Company office, which was located in the
Bank of America building. Robinson drew his handgun and
demanded money from a female employee, who informed him the
bank was next door. Robinson then put a gun to the woman’s back
and walked her outside and then into the bank. After Robinson
entered the bank, he released the employee, approached a teller,
handed her a pillowcase, and told her to fill it with money. The teller
put $13,226 in the pillowcase and also placed a dye pack in the pil-
lowcase. As Robinson fled through a wooded area behind the bank,
the dye pack exploded in the pillowcase. Robinson left the pillowcase
and the money in the woods and returned to Groves and Sanders.
Robinson later went back to look for the money, but it was gone. In
fact, police officers located the money shortly after the robbery. Also
recovered by police were a pair of gloves, a mask, and a handgun.

   On August 18, 2001, Sanders, Groves and Robinson were bored
and decided to drive around looking for something to rob. They set-
tled on the Food Lion in Fuquay-Varina, North Carolina. Groves sur-
veyed the store under the guise of requesting a job application. He
returned and told Sanders and Robinson the store layout. Sanders and
Robinson then donned masks and entered the store with guns drawn.
They obtained $2,000 from the store’s safe before fleeing.

   Next, on August 21, 2001, Robinson, Sanders, and Groves decided
to rob the First Citizens Bank in Smithfield, North Carolina. After
Sanders called a bomb threat to the local Wal-Mart to divert police
attention, Robinson entered the bank wearing a hood and carrying a
handgun. Robinson pointed the gun at a teller and handed her a pil-
lowcase to fill. The teller complied with Robinson’s demands and
6                    UNITED STATES v. ROBINSON
filled the pillowcase with money from her till. Robinson then exited
the bank carrying the pillowcase. Unfortunately for Robinson, how-
ever, a brave citizen followed him and called 911, informing officers
that Robinson had entered an apartment complex.

   Police in an unmarked car responded to the call and began patrol-
ling the apartment complex. The police came upon a slow-moving
vehicle with two individuals inside. Both were constantly looking out
the windows, as if searching for someone. The officers followed the
car until it stopped and the two individuals exited the car and entered
a nearby apartment. The officers approached the apartment and
received permission to search the premises. The officers discovered
the money, the pillowcase, and clothing that matched that worn by the
robber. Robinson, Sanders, and Groves were also inside the apart-
ment.

   The police arrested Robinson, Sanders, and Groves and took them
to the Smithfield Police Department where they were interviewed
separately. Robinson was informed of his juvenile Miranda rights and
stated that he understood those rights. Robinson refused to sign a
Miranda waiver form, but he agreed to answer questions. Robinson
also stated that he did not want a lawyer or his grandmother present.
Robinson initially denied participating in the robbery, but after being
told that Sanders and Groves were cooperating, Robinson admitted to
participating in the First Citizens Bank robbery, the December 20,
2000 Piggly Wiggly robbery, the December 27, 2000 Four Oaks Bank
robbery, the June 1, 2001, Bank of America robbery, and the August
18, 2001 Food Lion robbery.

   On March 19, 2002, the Government filed a twenty-eight count
juvenile information against Robinson. The information charged Rob-
inson with conspiracy to commit armed bank robbery, armed bank
robbery, attempted bank robbery, and various firearms and Hobbs Act
offenses. Both the Government and Robinson filed motions for com-
petency exams. The Government also filed a motion to transfer Rob-
inson to adult status for trial.

  Robinson was sent to the Dakota Horizons Youth Center (Dakota
Center) in North Dakota for evaluation, treatment, and detention.
While there, Dr. Alan Fehr, a clinical psychologist, performed a thor-
                       UNITED STATES v. ROBINSON                         7
ough psychiatric examination of Robinson. Dr. Fehr administered 15
tests to Robinson, including the Weschler Adult Intelligence Test -
3rd Edition. Robinson scored a 70 on this I.Q. test. Based on the
examination and testing, Dr. Fehr prepared a report concluding that
Robinson was competent to stand trial.

   Colby Braun, the director of the Dakota Center, testified that dur-
ing the two months Robinson spent at the Center, he was involved in
several altercations and verbal spats with other youths or with staff.
Braun also testified that Robinson told him he created a homemade
weapon in order to be "one up" on the other youths at the Dakota
Center. (J.A. at 117.) In Braun’s opinion, some of Robinson’s behav-
ior was that of an adult criminal.

   The district court held a hearing to determine Robinson’s compe-
tency to stand trial, and also to resolve the Government’s motion to
transfer Robinson to adult status. The district court granted the Gov-
ernment’s motion for transfer and concluded that Robinson was com-
petent to stand trial. The Government then filed a twenty-count
indictment against Robinson. Robinson was charged with three counts
of conspiracy, in violation of 18 U.S.C.A. § 371 (West 2000); three
counts of armed bank robbery, aiding and abetting, in violation of 18
U.S.C.A. § 2113(a) (West 2000); six counts of brandishing a firearm
during a crime of violence, in violation of 18 U.S.C.A. § 924(c) (West
2000); one count of attempted bank robbery, in violation of 18
U.S.C.A. § 2213(a)(2) (West 2000); five counts of interfering with
commerce by robbery, aiding and abetting, in violation of 18
U.S.C.A. § 1951 (West 2000); and two counts of discharging a fire-
arm during and in relation to a crime of violence, in violation of 18
U.S.C.A. § 924(c).

   Robinson refused the Government’s offer of a plea bargain,
pleaded not guilty, and continued to trial.2 The district court, upon the
Government’s motion, dismissed the count of attempted robbery.
Robinson was convicted on the remaining counts. After a sentencing
hearing, the district court granted Robinson’s request for a downward
  2
   Sanders and Groves both pleaded guilty to their roles in the robberies
and testified against Robinson at trial. Sanders received a sentence of 144
months imprisonment, and Groves received 96 months imprisonment.
8                      UNITED STATES v. ROBINSON
departure for diminished capacity over the Government’s objection
and sentenced Robinson to a total of 384 months imprisonment and
five years supervised release.

                                    II.

   On appeal, Robinson has raised numerous challenges to his convic-
tion and one challenge to his sentence. Robinson contends that he was
not competent to stand trial, that the district court should not have
transferred him to adult status, and that he was not competent to
waive his Miranda rights.3 Robinson also asserts that his sentence
violates the rule of United States v. Booker, 125 S.Ct. 738 (2005). The
Government has cross-appealed Robinson’s sentence, contending that
the district court erred in granting Robinson a downward departure for
diminished capacity, and in departing below the statutory minimum
provided for Robinson’s § 924(c) convictions.

                                   III.

    Robinson’s primary argument on appeal is that he was not compe-
tent to stand trial. We review the district court’s competency determi-
nation for clear error. United States v. Cox, 964 F.2d 1431, 1433 (4th
Cir. 1992). Courts examining the competency of a defendant must
determine if "[the defendant] has sufficient present ability to consult
with his lawyer with a reasonable degree of rational understanding
. . . and whether he has a rational as well as factual understanding of
the proceedings against him." Dusky v. United States, 362 U.S. 402
(1960). Under federal law the defendant has the burden, "by a prepon-
derance of the evidence [to show] that the defendant is presently suf-
fering from a mental disease or defect rendering him mentally
    3
    Robinson raises two other issues relating to his conviction that do not
warrant discussion. Robinson argues that the Government did not pro-
duce sufficient evidence to sustain the convictions and that the district
court committed reversible error in refusing to instruct the jury on the
defense of diminished capacity. We have reviewed the record, briefs, and
oral argument on these issues and find them to be clearly without merit.
There was overwhelming evidence of Robinson’s guilt, and Robinson
failed to submit sufficient evidence to permit the district court to give a
diminished capacity jury instruction.
                      UNITED STATES v. ROBINSON                        9
incompetent to the extent that he is unable to understand the nature
and consequences of the proceedings against him or to assist properly
in his defense." 18 U.S.C.A. § 4241(d) (West 2000). See also Cooper
v. Oklahoma, 517 U.S. 348, 362 (1996) ("Congress has directed that
the accused in a federal prosecution must prove incompetence by a
preponderance of the evidence.").

   The district court ruled that Robinson was competent because of
the un-rebutted testimony and report of Dr. Fehr. As noted, Dr. Fehr
performed an extensive psychological examination of Robinson and
prepared a report following that examination. Robinson’s I.Q., as
tested by Dr. Fehr, is 70, which is borderline functional. Robinson’s
previous I.Q. scores were 74 (age six), 90 (age nine), 87 (age eleven),
and 84 (age fourteen). Dr. Fehr noted repeatedly in his report that he
had difficulty evaluating Robinson because Robinson had trouble
staying on task and did not always appear to give full effort to the
testing. In addition, "James presented in a fairly dramatic manner,
perhaps to the point of being considered theatrical." (J.A. at 292.) Dr.
Fehr did note that Robinson had a variety of mental disorders, includ-
ing attention-deficit/hyperactivity disorder (ADHD), reading disorder,
mathematics disorder, expressive language disorder, provisional poly-
substance abuse, schizotypal personality disorder, and borderline
intellectual functioning. Dr. Fehr conceded "it is quite possible that he
has some subtle neurological problems," and "[i]t is also possible that
he has some borderline psychotic features." (J.A. at 294.)

    Dr. Fehr found Robinson’s "perceptions are faulty and his thinking
is odd and loose. However, he does not appear to be mentally ill
. . . . [Indeed, h]e appears to have at least a minimal understanding
of legal procedures, rules and expectations." (J.A. at 294) (emphasis
added.) Dr. Fehr also concluded that Robinson was not mentally
retarded and that he was "at least minimally able to understand the
nature and consequences of the proceedings against him." (J.A. at
294.) In addition, Dr. Fehr opined that "[Robinson] appears to be at
least minimally able to understand the nature and consequences of the
proceedings against him and to assist properly in his defense." (J.A.
at 294.)

   Dr. Fehr also testified during the competency hearing and reiterated
his opinion that Robinson was competent to stand trial. Dr. Fehr testi-
10                    UNITED STATES v. ROBINSON
fied: "I don’t believe that he has a psychotic disorder. [I do] believe
that he has what I’ve referred to or diagnosed as a schizo-typo [sic]
personality disorder which relates more to a personality style that
involves some looseness, some magical thinking, things of that
nature." (J.A. at 78.) Dr. Fehr felt that "[i]n terms of being minimally
competent . . . he came up above the line, but not much above the
line." (J.A. at 83.)

   Following this hearing, the district court ruled that Robinson was
competent, finding Dr. Fehr’s report and testimony persuasive. The
district court found that Robinson did not have a mental disease, was
not mentally retarded, and that Robinson, while lacking in academic
prowess, possessed "overall intellect or common sense." (J.A. at 211.)
In making this latter finding, the district court referred to "the planned
nature of the robberies, his wherewithal to hide out for several hours
after a robbery to prevent detection, as well as his ability to give an
alias to police." (J.A. at 211.)

   We do not believe that the district court clearly erred in reaching
this finding. Robinson had the burden of proving that he was incom-
petent to stand trial. The only expert before the district court, Dr.
Fehr, testified that Robinson was competent. Robinson contends that,
according to some of the testing performed by Dr. Fehr, he operates
at the level of an eleven year-old. The fact that some of Robinson’s
test scores indicate a low intellectual ability does not, however, under-
mine Dr. Fehr’s ultimate conclusion that Robinson was competent.
Robinson also points to the fact that, in response to a question on
cross-examination regarding whether Dr. Fehr had concluded that
Robinson was competent as a juvenile, Dr. Fehr stated his "assump-
tion of course was that [he] was asked to determine competency as
a juvenile." (J.A. at 85.) Given this statement, Robinson argues, Dr.
Fehr’s testimony is not relevant as to whether Robinson was compe-
tent to be proceeded against as an adult in federal district court. Rob-
inson’s argument, however, takes Dr. Fehr’s statement out of context
and, in any event, on redirect examination Dr. Fehr opined again that
Robinson was competent to stand trial. Moreover, even if Dr. Fehr’s
testimony loses some of its persuasive force because of this alleged
concession, we are left with the simple fact that Robinson failed to
put forth any evidence to support a finding that he was incompetent.
Although Robinson does appear to be of low intelligence and to have
                       UNITED STATES v. ROBINSON                          11
several mental disorders, we do not believe the district court clearly
erred in ruling that Robinson was competent to stand trial.

                                    IV.

   Robinson’s next argument is that the district court should not have
transferred him to adult status. Persons who violate federal criminal
laws before the age of eighteen are adjudged juvenile delinquents. 18
U.S.C.A. § 5031 (West 2000). The purpose of § 5031 is to "remove
juveniles from the ordinary criminal process in order to avoid the
stigma of a prior criminal conviction and to encourage treatment and
rehabilitation." United States v. Brian N., 900 F.2d 218, 220 (10th
Cir. 1990). Juveniles can, however, be transferred to adult status and
prosecuted in federal court when, relevant here, the Attorney General
"certifies to the appropriate district court that . . . the offense charged
is a crime of violence that is a felony . . . and that there is a substantial
Federal interest in the case or the offense to warrant the exercise of
federal jurisdiction." 18 U.S.C.A. § 5032 (West 2000). If such a certi-
fication is made, the district court can transfer the juvenile upon find-
ing, after a hearing, that "such transfer would be in the interest of
justice." Id. To make this determination, the district court examines
six factors: (1) the age and social background of the juvenile; (2) the
nature of the alleged offense; (3) the extent and nature of the juve-
nile’s prior delinquency record; (4) the present intellectual and psy-
chological development and maturity of the juvenile; (5) the nature of
past treatment efforts and the effect of such efforts; and (6) the avail-
ability of programs to treat the juvenile’s behavioral problems. Id. at
¶ 5.

   The Government has the burden of proving that a transfer would
be in the interest of justice by preponderance of the evidence. United
States v. Juvenile Male # 1, 86 F.3d 1314, 1323 (4th Cir. 1996) (Juve-
nile Male # 1 (4th Cir.)). The district court "may determine what
weight to give the various factors," although, "[i]n the weighing of the
various factors, the nature of the crime clearly predominates." Id. See
also United States v. One Juvenile Male, 40 F.3d 841, 845-46 (6th
Cir. 1994) (collecting cases). Ultimately, a court should "balance the
[rehabilitative] purposes against the need to protect the public from
violent and dangerous individuals." United States v. Juvenile Male #
1, 47 F.3d 68, 71 (2d. Cir. 1995) (Juvenile Male # 1(2d Cir.)). "A
12                    UNITED STATES v. ROBINSON
glimmer of hope in future treatment, standing alone, would be insuffi-
cient to warrant a finding that rehabilitation is likely." United States
v. Nelson, 68 F.3d 583, 590 (2d Cir. 1995).

   We review a district court’s ultimate decision to transfer a juvenile
to adult status for abuse of discretion. Juvenile Male # 1 (4th Cir.),
86 F.3d at 1324. "An abuse of discretion occurs if the district court
fails to make the required factual findings, or if those factual findings
are clearly erroneous." Juvenile Male # 1(2d Cir.), 47 F.3d at 71 (cita-
tions omitted).

   The district court conducted an extensive hearing before conclud-
ing that, in the interest of justice, Robinson should be transferred to
adult status. The district court concluded that four of the factors
weighed in favor of a transfer, one factor was neutral, and one favored
denying the transfer request. Specifically, the district court found that
Robinson’s age and social environment, the nature of the crimes
alleged, Robinson’s intellectual development and psychological matu-
rity, and Robinson’s response to past treatment efforts weighed in
favor of a transfer. The district court found that the availability of
juvenile programs was neutral given the unpredictability of open beds
at such facilities in the region, and that the Government had failed to
prove an extensive juvenile record.

   A review of the district court’s findings as to each factor leads us
to conclude that the district court did not abuse its discretion in trans-
ferring Robinson to adult status. First, we agree with the district court
that Robinson’s age and social environment favored a transfer. Robin-
son was 15 and 16 at the time he committed his crimes, and 18 at the
time of his transfer hearing. Robinson committed his crimes in North
Carolina, and under that state’s law, he also could have been tried as
an adult. N.C. Gen. Stat. § 7B-2200 (2003). Moreover, Robinson’s
grandmother testified that Robinson had a stable home life after he
moved in with her at the age of seven. Although Robinson’s early
years with his mother were not pleasant by any stretch of the imagina-
tion, Robinson had been provided with a loving home for eight years
prior to committing the crimes in question. We believe this factor
weighed in favor of a transfer.

   Most importantly, we agree with the district court’s determination
that the nature and severity of the alleged crimes weighed heavily in
                      UNITED STATES v. ROBINSON                       13
favor of a transfer. Robinson was charged with a number of serious,
violent crimes. As noted, in determining if a transfer is in the interest
of justice, the nature and severity of the crimes is the most important
factor. Robinson was charged originally with nine armed robberies,
and with discharging his weapon during at least two of those rob-
beries. He was alleged to have carried a firearm during each robbery.
Thus, the nature and severity of the crimes weighs heavily in favor
of transfer because it implies a need to protect the public. See Juvenile
Male # 1(2d Cir.), 47 F.3d at 71.

   Next, we do not believe the district court clearly erred in finding
that the third factor, Robinson’s prior delinquency record, weighed
against a transfer. We note, however, that while Robinson’s only
actual delinquent behavior occurred when he was found with 6.6
grams of marijuana on his person at school, this act occurred in the
midst of the robbery spree that resulted in Robinson’s federal prose-
cution. In addition, while Robinson had only one prior delinquent
behavior, "[Robinson’s] juvenile record, while perhaps not extensive,
is still a record." Juvenile Male # 1 (4th Cir.), 86 F.3d at 1323. None-
theless, because Robinson did have only one prior act of delinquency,
we will not disturb the district court’s finding that Robinson’s prior
delinquency record does not weigh in favor of a transfer.

    Turning to the fourth factor, we agree with the district court that
Robinson’s intellectual development and psychological maturity
weighed in favor of a transfer. The district court concluded that this
factor favored a transfer because, "[v]iewing the possibility of reha-
bilitation as the ultimate issue . . . . the defendant’s comportment
. . . reveals that defendant has not been amenable or interested in fur-
thering his education." (J.A. at 217.) We agree. While Robinson lacks
academic prowess, he was wiley enough to give a false name to a
police officer to avoid capture on one occasion and was able, on sev-
eral occasions, to wait substantial periods of time to be picked up by
the getaway car following robberies. Moreover, Colby Braun of the
Dakota Center, where Robinson was held following his arrest, testi-
fied that he believed some of Robinson’s behavior was that of an
adult criminal, and not a juvenile.

   Next, the district court found, and we agree, that the nature of past
treatment efforts and Robinson’s response to those efforts weigh
14                    UNITED STATES v. ROBINSON
heavily in favor of a transfer. Evidence adduced at the hearing indi-
cated that Robinson misbehaved everywhere he was sent. He was sus-
pended from the school for troubled youths, and he was in two fights
and several other verbal altercations during the two month period he
spent at the Dakota Center for juveniles. In fact, Robinson even fash-
ioned a homemade weapon during his time at the Dakota Center.
Thus, this factor too weighs in favor of a transfer.

   Finally, the district court did not clearly err in finding that the
availability of facilities to treat Robinson was a neutral factor. The
Government put forth the testimony of a probation officer, who testi-
fied that Shelby, Tennessee was the only regional facility with juve-
nile programs. Space was not always available at the facility, and it
only held juveniles until the age of 21. At the time of the hearing,
Robinson was eighteen and a half years old, and Dr. Fehr testified that
Robinson required at least five years of treatment in a residential
facility.

   Given the record before the district court, and its factual findings
on that record, we do not believe it abused its discretion in transfer-
ring Robinson to adult status.

                                  V.

   Robinson next contends that the district court erred by denying his
motion to suppress post-arrest statements given by Robinson to police
officers on August 21, 2001, in which he admitted complicity in sev-
eral of the robberies.4 Robinson contends that, because of his limited
intellectual ability, the Government failed to prove that he knowingly
waived his Miranda rights. When reviewing a district court’s suppres-
sion ruling, we review factual findings for clear error and the ultimate
legal question de novo. United States v. Holmes, 376 F.3d 270, 273
(4th Cir.), cert. denied 125 S.Ct. 633 (2004).
  4
   Robinson waived his juvenile Miranda rights and gave statements to
police officers on three occasions; January 12, 2001, January 30, 2001,
and August 21, 2001. On appeal, Robinson only contests the statements
given on August 21.
                       UNITED STATES v. ROBINSON                        15
   The Government has the burden of proving, by a preponderance of
the evidence, that the defendant’s waiver of his Miranda rights was
knowing and voluntary. The waiver must be "voluntary in the sense
that it was the product of a free and deliberate choice," and also it
must be made "with a full awareness of both the nature of the right
being abandoned and the consequences of the decision to abandon it."
Moran v. Burbine, 475 U.S. 412, 421 (1986). To determine whether
the Government has met its burden, we examine the "totality of the
circumstances." Id.

   Robinson does not contend that his waiver was involuntary, but
rather argues that, given his age at the time of the interrogation, and
his mental ability, he was per se incapable of knowingly waiving his
Miranda rights.

   The district court held a hearing on the suppression motion at
which Special Agent Hicks of the North Carolina State Bureau of
Investigation testified. Agent Hicks, who questioned Robinson on
August 21, testified that he read all of the juvenile Miranda rights to
Robinson and that Robinson indicated that he understood them. Rob-
inson responded that he did not want to sign a waiver of rights form,
but that he would answer questions. Robinson also declined a request
to notify his grandmother. Robinson did not indicate that he was
unable to understand his rights. Robinson testified at the suppression
hearing, however, that he agreed to answer questions from Agent
Hicks, but that he "didn’t know what that stuff means . . . [because]
[he had] never been through it before." (J.A. at 470.)

   In denying the motion to suppress, the district court noted Robin-
son "has an I.Q. score which is admittedly low," but "the defendant
is street wise and . . . fully conversant with his rights that were articu-
lated to him." (J.A. at 482.) The district court recognized Robinson
failed to sign the waiver of rights form, but concluded, "although the
waiver wasn’t signed by the defendant, I’m satisfied that he[,]having
been advised of these almost identical rights on two previous occa-
sions known by this Court[,]that he was advised on that occasion and
he properly waived his rights." (J.A. at 482.)

  We do not believe that the district court erred by denying Robin-
son’s motion to suppress. Robinson’s below average I.Q. does not
16                   UNITED STATES v. ROBINSON
make him per se incapable of intelligently waiving his rights. See
Moore v. Dugger, 856 F.2d 129, 134-35 (11th Cir. 1988) (upholding
waiver of rights by defendant with I.Q. of 62 and intellectual capacity
of an eleven year old). In cases involving defendants with low intel-
lectual ability, the knowingness of the waiver often turns on whether
the defendant expressed an inability to understand the rights as they
were recited. In United States v. Rosario-Diaz, 202 F.3d 54 (1st Cir.
2000), the First Circuit upheld the denial of a suppression motion
involving a woman with an IQ in the 70s and no prior experience with
the criminal justice system because the officers testified that the
woman understood the questions and rights. Id. at 69. See also United
States v. Male Juvenile, 121 F.3d 34, 40 (2d Cir. 1997) (finding
waiver was knowing for juvenile with attentional and learning disabil-
ities because juvenile indicated that he understood the rights as they
were being read to him).

   In this case, Robinson indicated that he understood his rights as
they were recited. Robinson had, on two prior occasions, been read
his Miranda rights and waived them. See United States v. Cristobal,
293 F.3d 134, 142 (4th Cir. 2002) (noting relevance that suspect had
previously been given Miranda rights). On one of those occasions,
Robinson’s grandmother was also present during the reading of the
rights. For a waiver to be knowing, Robinson need only understand
"both of the nature of the right being abandoned and the consequences
of the decision to abandon it." Colorado v. Spring, 479 U.S. 564, 573
(1987) (quotation omitted). Although Robinson admittedly has a low
I.Q. and several mental disorders, nothing in the record indicates that
Robinson could not understand the rights as Agent Hicks provided
them. To the contrary, the record reveals, as the district court
explained, that Robinson was "street smart" and understood his
Miranda rights.

                                 VI.

   Finally, Robinson argues that he was sentenced in violation of the
Supreme Court’s recent ruling in Booker. On cross-appeal, the Gov-
ernment argues that the district court erred by granting Robinson a
downward departure under the United States Sentencing Guidelines
for diminished capacity because this downward departure led the dis-
trict court to impose Robinson’s sentences for violations of § 924(c)
                      UNITED STATES v. ROBINSON                       17
concurrently instead of consecutively as statutorily required. Because
we find merit in the Government’s contention, we remand the case for
resentencing. On remand, the district court should comply with the
remedial scheme adopted by the Court in Booker in sentencing Robin-
son. See United States v. Hughes, 2005 WL 628224, * 4 (4th Cir.
March 16, 2005).

   During the sentencing hearing, the district court stated that Robin-
son’s Guidelines sentence was approximately 193 years. That sen-
tence was calculated as follows: 84 months for the first § 924(c)
conviction, 300 months consecutive for the seven additional § 924(c)
convictions, and 135 months for the armed robbery counts. The dis-
trict court then, over the Government’s objection, granted Robinson
a downward departure for diminished capacity. The district court sen-
tenced Robinson to 384 months imprisonment, running only the first
§ 924(c) conviction and one additional § 924(c) conviction consecu-
tively.
   Thus, the district court’s decision to depart led it to run Robinson’s
§ 924(c) convictions concurrently. Section 924(c)(1)(D)(ii), however,
provides, in relevant part, that "no term of imprisonment imposed on
a person under this subsection shall run concurrently with any other
term of imprisonment imposed on the person." 18 U.S.C.A.
§ 924(c)(1)(D)(ii). Accordingly, the statute mandates that each sen-
tence for convictions under § 924(c) must be imposed consecutively.
See also Cristobal, 293 F.3d at 146 n.19. Section 924(c) also sets out
statutory minimum sentences for violations. Section 924(c)(1)(A)(ii)
provides for a mandatory term of imprisonment of not less than seven
years if the firearm was brandished during the commission of a crime
of violence. Moreover, "[i]n the case of a second or subsequent con-
viction under this subsection, the person shall — be sentenced to a
term of imprisonment of not less than 25 years." 18 U.S.C.A.
§ 924(c)(1)(C)(i). Robinson’s first conviction for brandishing a fire-
arm during a crime of violence thus necessitated a statutory minimum
sentence of seven years. Each of the seven additional convictions
under § 924(c) required statutory minimum sentences of 25 years to
run consecutively to each other. Thus, under the statutory scheme
enacted by § 924(c), Robinson faced a statutory minimum sentence of
2184 months, or 182 years. Any sentence entered for the substantive
18                    UNITED STATES v. ROBINSON
robbery convictions must also run consecutive to that sentence. 18
U.S.C.A. § 924(c)(1)(D)(ii).
   Booker did nothing to alter the rule that judges cannot depart below
a statutorily provided minimum sentence. Except upon motion of the
Government on the basis of substantial assistance, a district court still
may not depart below a statutory minimum. See 18 U.S.C.A.
§ 3553(e) (West 2000). In this case, the district court sentenced Rob-
inson to 384 months, over one-hundred years below the mandatory
statutory minimum. Even though, after Booker, sentences outside of
the guidelines range should be upheld when that sentence is a "rea-
sonable" exercise of discretion, see Booker, 125 S.Ct. at 765, a district
court has no discretion to impose a sentence outside of the statutory
range established by Congress for the offense of conviction.
   Because the district court departed below the statutory minimum,
we must remand the case for resentencing. As the preceding discus-
sion makes clear, Robinson is facing at least 2184 months of impris-
onment for his crimes. While this result may seem manifestly unjust
given Robinson’s age and well-documented intellectual limitations, it
is the result mandated by Congress.5
                                  VII.
  We affirm Robinson’s conviction in full but reverse the district
court’s decision to sentence Robinson below the statutory minimum
mandated by his multiple convictions for violating § 924(c) and
remand the case for resentencing.
     AFFIRMED IN PART, REVERSED IN PART, AND REMANDED
  5
   Robinson’s mandatory-minimum sentence under § 924(c)(1)(C)(I)
and (D)(ii) is considerably longer than the sentences received by his co-
defendants and the one he apparently would have received had he
pleaded guilty. At oral argument, the parties stated that the Government
offered Robinson a plea agreement entailing a sentence of less than
twenty years. According to statements made during oral argument, the
defendant and the Government agreed to this plea deal, but Robinson
refused to properly complete a Rule 11 colloquy with the district court.
Accordingly, because Robinson chose to proceed to trial, rather than face
less than twenty years in prison, he is subject to this extraordinarily
lengthy sentence.
