August 3, 1994    UNITED STATES COURT OF APPEALS
                    FOR THE FIRST CIRCUIT

                                     

No. 93-2232

                        UNITED STATES,

                          Appellee,

                              v.

                    DARYL E. SINGLETERRY,

                    Defendant, Appellant.

                                     

                         ERRATA SHEET

   The  opinion of  this  court issued  on  July 18,  1994,  is
amended as follows:

   Page 4, third  line from the bottom:  Replace "Fed. R. Crim.
P. 39(a)" with "Fed. R. Crim. P. 29(a)."

                United States Court of Appeals
                    For the First Circuit
                                         

No. 93-2232

                        UNITED STATES,

                          Appellee,

                              v.

                    DARYL E. SINGLETERRY,

                    Defendant, Appellant.

                                         

         APPEAL FROM THE UNITED STATES DISTRICT COURT

                  FOR THE DISTRICT OF MAINE

           [Hon. Gene Carter, U.S. District Judge]
                                                 

                                         

                            Before

                   Torruella, Circuit Judge,
                                           
                Coffin, Senior Circuit Judge,
                                            
                   and Stahl, Circuit Judge.
                                           

                                         

Stephen H. MacKenzie for appellant.
                    
Michael M.  DuBose, Assistant  United States  Attorney, with  whom
                  
Jay P. McCloskey, United States Attorney, was on brief for appellee.
            

                                         

                        July 18, 1994
                                         

          STAHL, Circuit Judge.   In this appeal,  defendant-
                              

appellant  Daryl E. Singleterry  contests his jury conviction

and  resulting   sentence  for  violation   of  federal  drug

trafficking  laws.   Singleterry  raises two  issues for  our

consideration.   First,  he  protests  the  district  court's

refusal  to  instruct  the  jury  to  determine  whether  the

prosecution  produced  sufficient evidence  to  establish the

trustworthiness of his  voluntary, extrajudicial  confession.

Second,  Singleterry,  who  is  black,  maintains   that  his

sentence violates the equal protection component of the Fifth

Amendment  because the  difference in punishment  for cocaine

base  ("crack")  offenses   and  cocaine  ("cocaine  powder")

offenses  is  either irrational  or  racially discriminatory.

Finding neither argument persuasive, we affirm.

                              I.
                                

                          BACKGROUND
                                    

          On January 14, 1993, Maine law enforcement  agents,

responding  to reports  of drug  dealing at  the Days  Inn in

Kittery, Maine,  commenced surveillance  of the motel.   That

evening,  they   observed  Jamee  Landry,  an   associate  of

Singleterry,  exit  Room  225  with  George  Wilson,  another

Singleterry  associate and  suspected drug  dealer.   The two

entered Landry's car and  drove to Portsmouth, New Hampshire,

where the agents lost  their trail.  Early the  next morning,

                             -2-
                              2

after they saw  Landry enter  Room 225,  the agents  executed

warrants to search both Room 225 and Landry's car.

          The search revealed a  number of items probative of

ongoing, armed  drug trafficking.   The agents  first entered

and  searched  Room 225,  where  they  found Singleterry  and

Landry.     They  seized   $2061  and  a   wallet  containing

Singleterry's driver's license from the pocket of a jacket on

a night table in the room.  Elsewhere in the room, the agents

discovered   two   savings   account   passbooks,   both   in

Singleterry's name, with  a combined  balance of  $5100.   In

Landry's  car, the agents found a plastic bag containing 6.46

grams of  crack cocaine in  the glove compartment,  a leather

gun holster on the front  passenger seat, as well as  a fully

loaded semi-automatic handgun under the same seat.

          After  this search  concluded, the  agents arrested

Singleterry,  and  properly  informed  him  of  his  "Miranda
                                                             

rights."    Singleterry  then  provided  the  agents  with  a

voluntary confession  telling them  that  he personally  paid

$250  to  his  source  in Lawrence,  Massachusetts,  for  the

cocaine base found in the vehicle.  He  also admitted that he

had stolen the handgun seized  by the agents, explaining that

he needed the handgun to protect himself from individuals who

were  jealous   of  his  cocaine  business.     In  addition,

Singleterry told  the agents that he did not have a job, that

he had been dealing cocaine base for a considerable period of

                             -3-
                              3

time, and that the cash seized from his jacket pocket as well

as the money in  his savings accounts were proceeds  from his

sale of cocaine base in  the Portsmouth, New Hampshire, area.

Finally,  Singleterry stated  that, as  in this  instance, he

purchased most of the cocaine base  he sold from a source  in

Lawrence or Lowell, Massachusetts.  According to Singleterry,

he would ordinarily pay  $250 for a quarter ounce  of cocaine

base and then sell it for $1250.

          Singleterry was charged in a three count indictment

with possession with intent  to distribute cocaine, 21 U.S.C.

    841(a)(1) and  841(b)(1)(B)(iii) (1988  &amp; Supp.  IV 1992)
                 

(Count  I), the use and  carrying of a  firearm in connection

with a drug trafficking  offense, 18 U.S.C.   924(c)  (1988 &amp;

Supp.  IV 1992)  (Count  II), and  deriving certain  personal

property  from  proceeds  obtained  as  the  result  of  drug

trafficking  activity, 21  U.S.C.    853 (1988)  (Count III).

The  parties agreed to  have the district  court decide Count

III on the basis of the trial evidence.

          At  trial,  the   government  introduced   evidence

probative of  the facts  described above, relying  heavily on

the   agents'   live   testimony   concerning   Singleterry's

confession.   At the close of the government's case in chief,

the defense moved  for judgment  of acquittal.   See Fed.  R.
                                                    

Crim. P. 29(a).  Defendant's primary contention was  that the

government's  evidence  could   not  suffice  to   support  a

                             -4-
                              4

conviction   because  the   government  did   not  adequately

corroborate  Singleterry's confession.   See Opper  v. United
                                                             

States, 348  U.S. 84  (1954) (prohibiting convictions  on the
      

basis of uncorroborated confessions).  The government argued,

inter alia, that there was  ample evidence to demonstrate the
          

truth and  accuracy of the  confession.   The district  court

reserved judgment until the close of all the evidence.  After

the  defense  presented   no  evidence,   the  court   denied

defendant's motion in a detailed ruling from the bench.

          Singleterry  timely  requested  a jury  instruction

that "as a matter of law a confession alone is not sufficient

evidence  upon  which  to  convict the  defendant,  that  the

confession  must be  accompanied by  additional corroborative

[evidence]  or  sufficient  indicia  of  reliability."    The

district  court  refused  to   do  so,  explaining  that  the

corroboration  inquiry is  for the  court and  not  the jury.

According  to the  district court,  the role  of the  jury is

simply  to  consider whether  the  evidence establishes  each

element of  the offense  beyond a reasonable  doubt, although

the  jury  is  free to  question  the  probative  value of  a

confession  in  light of  the  strength  or weakness  of  the

corroborative evidence.

          After deliberating for less  than an hour, the jury

convicted Singleterry on Counts I and II.  The district court

later issued an orderof forfeiture in resolution ofCount III.

                             -5-
                              5

          At sentencing, the  district court  found that  the

offense  level, including relevant  conduct, involved a total

of 73.66 grams of  cocaine base, resulting in a  base offense

level of 32.  United States Sentencing Commission, Guidelines
                                                             

Manual,      2D1.1  (Nov.  1993);   see  also  21   U.S.C.   
                                             

841(b)(1)(B)  (prescribing  minimum  and maximum  sentences).

Because Singleterry had knowingly  given false testimony at a

pre-trial suppression hearing,  the court  added a  two-level

enhancement for  obstruction of  justice.  U.S.S.G.    3C1.1.

With a total adjusted base offense level of 34 and a criminal

history category of III,  the guideline range on Count  I was

188  to  235 months.1   U.S.S.G.  Ch.5,  Pt.A.   The district

court selected  the minimum sentence of  188 months, imposing

as  well the  consecutive 60  month sentence  mandated by  18

U.S.C.   924(c) for  the firearm offense.  In  another ruling

from the  bench,  the district  court rejected  Singleterry's

argument that stiffer penalties for cocaine base offenses, as

opposed  to cocaine  powder  offenses, violate  Singleterry's

right to equal protection of the law.

                    

1.  If  Singleterry had  been  convicted of  possession  with
intent  to distribute  cocaine  powder, and  if his  relevant
conduct raised the total of cocaine powder involved to  73.66
grams, his base offense level would have been 16, adjusted to
18 after the two-level  enhancement.  U.S.S.G.   2D1.1  and  
                                                           
3C1.1; see also 21 U.S.C.   841(b)(1)(C) (prescribing maximum
               
sentences).   With a criminal  history category  of III,  the
guideline  range on  this  count would  have  been 33  to  44
months.

                             -6-
                              6

                             II.
                                

                          DISCUSSION
                                    

A.  Trustworthiness of Confessions and the Role of the Jury 
                                                           

          Singleterry  contends  that   the  district   court

committed legal error when it refused to instruct the jury on

the need for corroboration  of his confession.  Specifically,

Singleterry  urges  us  to  adopt one  of  two  propositions.

First,  he suggests  that, when  the government's  case rests

primarily on  a  defendant's confession,  the district  court

must  instruct  the  jury  to  find   the  confession  to  be

trustworthy before  considering  it  as  evidence  of  guilt.

Second, Singleterry  asserts that, even  in the absence  of a

general  rule mandating  such  an  instruction, the  district

court is  obliged to instruct  the jury on  the corroboration

requirement where the evidence  of trustworthiness is so weak

that a jury  might differ from the court in its resolution of

the question.

          Whether the  court must assign  such a role  to the

jury is a  pure question  of law subject  to plenary  review.

See,  e.g., United States  v. Gallo, 20 F.3d  7, 11 (1st Cir.
                                   

1994) (holding that de novo review is customary for questions
                           

of law) (citing  In re Howard, 996 F.2d 1320,  1327 (1st Cir.
                             

1993)).   Thus, although  the district court's  reasoning may

prove persuasive,  and its conclusion coincide  with our own,

                             -7-
                              7

we are  free to reject  a reasonable  reading of  the law  in

favor of the interpretation we view as correct.

          To  begin  with, we  note  that  a defendant's  own

statements are never considered to be hearsay when offered by

the government; they are  treated as admissions, competent as

evidence  of guilt  without  any special  guarantee of  their

trustworthiness.   See  Fed.  R. Evid.  801(d)(2) &amp;  advisory
                      

committee's  note; see  also United  States v.  Barletta, 652
                                                        

F.2d  218, 219  (1st Cir.  1981).   Nevertheless, there  is a

danger that the jury will rush to credit a confession without

seriously  considering whether  the defendant confessed  to a

crime he  did not commit.   As a  result, the  federal courts

have adopted common law rules designed to prevent a jury from

convicting  the   defendant  solely   on  the  basis   of  an

untrustworthy confession.   The general  rule is that  a jury

cannot  rely  on an  extrajudicial,  post-offense confession,

even  when   voluntary,  in  the   absence  of   "substantial

independent  evidence  which  would  tend  to  establish  the

trustworthiness of [the] statement."  Opper v. United States,
                                                            

348 U.S. 84, 93 (1954).  See also Smith v. United States, 348
                                                        

U.S. 147  (1954); Warszower  v. United  States, 312  U.S. 342
                                              

(1941); United States  v. O'Connell, 703  F.2d 645 (1st  Cir.
                                   

1983).2   The Court has  explained that independent  proof of

                    

2.  Many states  adhere to a more  traditional formulation of
the corroboration  rule, requiring independent  proof of  the
corpus  delicti   ("body  of  the  crime"),   i.e.,  evidence
                                                  

                             -8-
                              8

the commission of the  charged offense is not the  only means

of  establishing  the  trustworthiness  of   the  defendant's

confession; another  "available mode of  corroboration is for

the independent evidence to bolster the confession itself and

thereby  prove the  offense `through'  the statements  of the

accused."  Smith, 348 U.S. at 156.3
                

          The doctrinal nature and procedural concomitants of

the trustworthiness requirement  announced in  Opper are  not
                                                    

entirely clear.   Traditionally,  the district court  makes a

preliminary determination  as to whether  testimony about the

confession  is  sufficiently  trustworthy  for  the  jury  to

consider the confession as evidence  of guilt.  See McCormick
                                                             

   145,  at  562;  Corey J.  Ayling,  Comment,  Corroborating
                                                             

Confessions:  An  Empirical  Analysis  of   Legal  Safeguards
                                                             

                    

independent of the confession showing that "(a) the injury or
harm constituting  the crime occurred; [and]  (b) this injury
or  harm was  done in  a  criminal manner."   1  McCormick on
                                                             
Evidence    145,  at 557  (John William  Strong ed.,  4th ed.
        
1992) (hereinafter "McCormick").
                             

3.  Singleterry misinterprets this comment as suggesting that
a full  confession (one involving admissions  to all elements
of the crime) automatically bolsters  itself, eliminating the
need for proof of trustworthiness.  According to Singleterry,
"under  Opper and Smith, the prosecution may rely entirely on
                       
a confession which is  not even proven to be  trustworthy and
put forth no evidence establishing the corpus delicti."  This
is simply  not so.   The Court  has never  suggested that  in
certain cases the government would be relieved of the  burden
of proving the trustworthiness of a confession.  Smith merely
                                                      
stands for the proposition that in the absence of independent
evidence of  the corpus delicti the  government may establish
                               
the  trustworthiness of  the confession  with other  evidence
typically used to bolster  the credibility and reliability of
an out-of-court statement. 

                             -9-
                              9

Against  False  Confessions, 1984  Wis.  L.  Rev. 1121,  1140
                           

(hereinafter  "Ayling").   In  this respect,  the Opper  rule
                                                       

essentially functions as a federal common law rule regulating

the  admission of  statements which  "are much  like hearsay,

[having  had] neither the compulsion of the oath nor the test

of  cross-examination."   Opper, 348  U.S. at  90.   See also
                                                             

Ayling,  supra,   at  1136-37   &amp;  n.66  (arguing   that  the
              

corroboration    rule    "governs   the    admissibility   of

evidence").4

                    

4.  Note that Federal Rule  of Evidence 804(b)(3) provides an
important parallel.   Under  Rule 804(b)(3), a  confession by
someone  other  than  the   accused  is  treated  as  hearsay
admissible  as evidence  of guilt  if certain  conditions are
satisfied.   Rule 804(b)(3) rests on the  assumption that, in
general, "persons  will not make damaging  statements against
themselves  unless they  are true."   4  Jack B.  Weinstein &amp;
Margaret A. Berger, Weinstein's  Evidence   804(b)(3)[01], at
                                         
804-138  (1993).   But such  a confession  cannot be  used to
prove the defendant's guilt unless its use is necessitated by
the unavailability  of the declarant for courtroom testimony.
Fed.  R.  Evid.  804(b).     Additionally,  we  are  wary  of
individuals  who, as  a result  of mental  illness, a  fit of
passion, a misplaced sense  of sacrifice, or sheer mendacity,
falsely  incriminate themselves  in order  to spare  another.
Thus,  "[a]  statement tending  to  expose  the declarant  to
criminal liability  and offered  to exculpate the  accused is
not  admissible  unless  corroborating circumstances  clearly
indicate  the trustworthiness  of  the statement."   Fed.  R.
Evid.   804(b)(3).     It  is   also  significant   that  the
trustworthiness criterion of Rule 804(b)(3) is "cast in terms
of a requirement preliminary to admissibility," Fed. R. Evid.
804(b)(3) advisory  committee's note.  As  such, the district
court  makes the  first  and only  official determination  of
trustworthiness, although  it may  be proper to  instruct the
jury that statements admissible under Rule 804(b)(3) "must be
carefully scrutinized, weighed with  great care, and received
with  caution."  United States v. Miller, 987 F.2d 1462, 1465
                                        
(10th Cir. 1993).

                             -10-
                              10

          At  the  same   time,  courts  often   characterize

corroboration  requirements as  governing the  sufficiency of
                                                          

the  evidence.   See,  e.g., Warszower,  312  U.S. at  347-48
                                      

(holding that "[a]n uncorroborated confession . . . does  not

as  a matter of law  establish beyond a  reasonable doubt the

commission  of  a  crime");  O'Connell, 703  F.2d  at  647-48
                                      

(analyzing  corroboration issue  in  rejecting  challenge  to

sufficiency of evidence); McCormick, supra,   145, at 561-63.
                                          

In  contrast to  a simple  rule of  admissibility, a  rule of

sufficiency  might theoretically  allow  the trial  judge  to

instruct the  jury  to make  the  final determination  as  to

whether  a  confession  has   been  corroborated.    See  id.
                                                             

(reporting  that some  state courts  treat the  corroboration

requirement as a jury issue); Ayling, supra, at 1136-41.  The
                                           

Supreme Court has not ruled on the question, and neither this

circuit nor  any  other  circuit has  adopted  such  a  broad

approach.   But cf. United States v. Marshall, 863 F.2d 1285,
                                             

1287 (6th  Cir. 1988) (holding that the district court should

have  instructed the  jury on  the  corroboration requirement

where "[t]he need for corroboration [was] apparent").

          It is within the uncertain framework of sufficiency

that Singleterry positions his  appeal.  Singleterry does not

claim that the district court  erred in admitting evidence of

his confession.  Nor  does he assert that the  district court

improperly   found   that  the   confession   was  adequately

                             -11-
                              11

corroborated   in   denying  the   motion  for   judgment  of

acquittal.5   Rather, Singleterry insists that,  even after a

court  has properly  admitted  evidence of  a confession  and

correctly tested the sufficiency of the evidence to support a

conviction, the  court has a responsibility, either generally

or in certain cases,  to instruct the jury to  determine that

the  confession  is  trustworthy  before  considering  it  as

evidence  of  guilt.   This has  never  been the  law  in the

federal courts, and we decline to adopt such a rule today.  

                    

5.  Two  paragraphs  in Singleterry's  opening  brief suggest
that  his  appeal comprehends  a  challenge  to the  district
court's  denial of  the motion  for acquittal.   Nonetheless,
Singleterry's reply  brief  states  that  "Appellant  is  not
arguing that the  evidence was insufficient for  the court to
determine that the corpus delicti existed.   Appellant is not
arguing  that . . . no rational  trier of fact could find the
corpus  delicti sufficient."   In  any event, it  is apparent
that  the  district court  did not  err  in finding  that the
government's    evidence     adequately    established    the
trustworthiness  of Singleterry's  confession.  Proof  of the
presence  in Landry's car of 6.46  grams of cocaine base -- a
controlled  substance in  an  amount  substantial  enough  to
suggest an intent to distribute --  independently establishes
the  corpus delicti  with respect  to Count  I.   No  more is
                   
required  to demonstrate the trustworthiness of Singleterry's
confession  to the  tangible crime  of possession  of cocaine
base  with  intent to  distribute.   See  Wong Sun  v. United
                                                             
States,  371  U.S.  471,  489-90  n.15   (1963).    That  the
      
confession is  trustworthy concerning admissions  relative to
Count  I  is strong  evidence  that  the  same confession  is
equally trustworthy concerning other admissions; namely, that
Singleterry used  the gun  found in  Landry's car  to protect
himself from rival drug dealers.  Even if that admission were
not sufficient to show that Singleterry "use[d] or carrie[d]"
the  gun  "in  relation   to"  his  possession  and  intended
distribution of the 6.46  grams of cocaine base, 18  U.S.C.  
924(c)(1),   the  government's  other  physical  evidence  --
particularly the proximity of Singleterry's loaded gun to the
cocaine  base -- would most  certainly allow a  jury to reach
that conclusion beyond a reasonable doubt.

                             -12-
                              12

          Although we cannot  accept Singleterry's theory  as

such, we do not mean  to suggest that the district  court has

no continuing  duty to police  the jury's consideration  of a

confession's probative  value.  First, if  the district court

loses  confidence  in  its   earlier  determination  of   the

corroboration issue and the  evidence is otherwise inadequate

to  support a conviction, the proper course would be to enter

a judgment of acquittal.   Alternatively, if the government's

remaining evidence could support  a finding of guilt but  the

jury's incurable  exposure to the  confession raises  serious

questions  about the  prospect of  a  fair trial,  the proper

course would be to declare a mistrial.  See Stewart v. United
                                                             

States, 366 U.S. 1, 10 (1961); United States v. Sepulveda, 15
                                                         

F.3d 1161,  1184 (1st Cir.  1993), cert. denied,  62 U.S.L.W.
                                               

    (U.S. June 20, 1994).

          Second,  a  confession  otherwise admissible  under

Opper  may nevertheless  be  inadmissible "if  its  probative
     

value  is substantially  outweighed by  the danger  of unfair

prejudice."  Fed. R. Evid. 403.6

          Third,   particularly   where  a   full  confession

dominates the government's proof, it is fair to assume that a

jury  will  interpret  its  duty  to  find  guilt  beyond   a

reasonable  doubt to  mean  that it  cannot  simply accept  a

                    

6.  Singleterry does  not argue  on appeal that  the district
court should have excluded evidence of the confession, or any
portion thereof, on Rule 403 grounds.

                             -13-
                              13

confession at face value.  See D'Aquino v. United States, 192
                                                        

F.2d  338, 357 (9th Cir.  1951) (holding that  where there is

adequate   corroboration  of   the   confession  "the   usual

instructions on presumption of innocence and reasonable doubt

adequately cover[] all that  the jury need be told  upon this

question  of  [corroboration]")  (citing Pearlman  v.  United
                                                             

States,  10 F.2d 460 (9th Cir. 1926)), cert. denied, 343 U.S.
                                                   

935  (1952); McCormick, supra,    145, at 564  ("Nor is there
                             

sufficient need to submit the matter to the  jury, as long as

the jury is  adequately sensitized  to the need  to find  all

elements of the crimes charged beyond a reasonable doubt.").

          Fourth, we note  that a judge has  wide latitude to

select  appropriate, legally  correct instructions  to ensure

that  the  jury  weighs the  evidence  without  thoughtlessly

crediting an  out-of-court confession.  Cf.  Miller, 987 F.2d
                                                   

at 1465 (holding that district court properly instructed jury

that  it  could rest  guilty  verdict  on uncorroborated  yet

credible testimony  of an accomplice but should "keep in mind

that such testimony is always to be received with caution and

weighed  with great care"); United States v. Twomey, 884 F.2d
                                                   

46, 53 (1st Cir. 1989) (suggesting that court may "assist the

jury by demonstrating to  them how to go about  analyzing the

evidence"), cert. denied, 496 U.S. 908 (1990); Ayling, supra,
                                                            

at  1141 (arguing that "guidance on  the means of determining

the  ultimate credibility  of the  evidence accords  with the

                             -14-
                              14

jury's   role   as  finder   of   evidentiary  sufficiency").

Accordingly, even if the district court has properly admitted

evidence of  a confession,  the court  has the  discretion to

determine  that the  question  of trustworthiness  is such  a

close one that it  would be appropriate to instruct  the jury

to conduct its own corroboration analysis.

          In  this  case, there  is  no  indication that  the

district court  overlooked its  obligation to avoid  or limit

undue  prejudice  stemming  from  evidence  of  Singleterry's

confession.  The  district court had  no occasion to  exclude

the  confession  under Rule  403,  correctly  found that  the

confession was  trustworthy, and properly instructed the jury

on  the  government's  burden  of  proof.    Finally,  in   a

manifestly  appropriate  exercise  of  discretion,  the court

directed  the  jury  to   "consider  any  .  .  .   facts  or

circumstances  disclosed by  the evidence  . .  .  tending to

corroborate or to contradict the version of  events which the

witnesses have told you."

          In sum, there  was no  error in  the lower  court's

refusal   to   instruct  the   jury   to   apply  the   Opper
                                                             

trustworthiness requirement  before considering Singleterry's

confession to be probative of his guilt.

B.    Constitutionality  of  Sentencing  Distinction  Between
                                                             
Cocaine Base and Cocaine Powder
                               

          Singleterry maintains that his  sentence on Count I

is  the  product of  an unconstitutional  distinction between

                             -15-
                              15

offenses involving cocaine  base and those involving  cocaine

powder.    See  18  U.S.C.     841(b);  U.S.S.G.     2D1.1(c)
              

(equating  1 gram of cocaine base with 100 grams of cocaine).

Singleterry  did not contend below that the laws at issue are

facially unconstitutional.  Instead,  he offered evidence  in

an  attempt to  demonstrate that  the sentencing  distinction

between  cocaine  base  and  cocaine  is  either  irrational,

racially  motivated,  or   both.    On  appeal,   Singleterry

essentially  argues  that   the  district  court  erroneously

applied the  relevant constitutional principles  to the facts

found at  the  sentencing  hearing.    We  first  recite  the

procedural rules  that govern  this portion of  our analysis,

then turn to a brief discussion of the merits.

          While pure questions of law  are subject to de novo
                                                             

review, we generally  examine a  district court's  fact-based

determinations for clear  error.  Williams v. Poulos, 11 F.3d
                                                    

271, 278 (1st Cir. 1993); In re  Howard, 996 F.2d at 1327-28.
                                       

Thus, the district court's findings of fact are conclusive on

appeal  "unless,  after  carefully  reading  the  record  and

according due deference to the trial court's superior ability

to judge  credibility, we  form `a strong,  unyielding belief

that a  mistake has been  made.'"   Williams, 11 F.3d  at 278
                                            

(quoting Dedham  Water Co.  v. Cumberland Farms  Dairy, Inc.,
                                                            

972  F.2d 453,  457 (1st Cir.  1992)).  The  same standard of

review  often applies  to mixed  questions of  law  and fact,

                             -16-
                              16

although  we are less likely to defer to the district court's

conclusions where  proper  application of  the law  primarily

requires a  clarification of the  relevant legal  principles.

Id. at 278 &amp; n.11 (citing In re Howard, 996 F.2d at 1328).
                                      

          The clear error standard  does not apply,  however,

when  the fact-finding  at issue  concerns "legislative,"  as

opposed to "historical" facts.  See generally Dunagin v. City
                                                             

of Oxford, 718 F.2d  738, 748 n.8 (5th  Cir. 1983) (en  banc)
         

(plurality), cert.  denied, 467  U.S. 1259 (1984);  Menora v.
                                                          

Illinois  High  Sch. Ass'n,  683  F.2d 1030,  1036  (7th Cir.
                          

1982),  cert. denied, 459 U.S. 1156 (1983); see also Lockhart
                                                             

v.  McCree,  476  U.S.  162,  168-69  n.3  (1986)  (reserving
          

question while  suggesting approval  of plurality  opinion in

Dunagin).       "Legislative   facts    are   those   general
       

considerations that  move a  lawmaking or rulemaking  body to

adopt  a rule,  as distinct  from the  facts  which determine

whether the rule was correctly applied."  Menora, 683 F.2d at
                                                

1036.   Accordingly, we need  not defer to  the lower court's

assessment   of  the   "evidence"   Singleterry   offers   to

demonstrate the irrational and racially discriminatory nature

of the adoption  of the distinction between  cocaine base and

cocaine powder offenses.

     1.  Irrational Classification
                                  

          It   is    well   settled   that    an   irrational

classification  imposed by  federal law  is violative  of the

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                              17

equal  protection  component  of  the Fifth  Amendment's  Due

Process  Clause.  See  Miranda v. Secretary  of Treasury, 766
                                                        

F.2d 1, 6  (1st Cir. 1985) (citing Mathews v.  De Castro, 429
                                                        

U.S.  181,  182 n.1  (1976)).   Singleterry  contends  that a

distinction between cocaine base and cocaine powder is such a

classification  because the  use  of  cocaine base  allegedly

presents no  greater health  threat than  the use of  cocaine

powder.   Yet Singleterry  presents little or  no evidence to

support  this  contention,  nor  has he  explained  why  such

evidence  would  be dispositive  of  the  rationality of  the

distinction at issue.

          Even  if  there is  no  telling  difference in  the

health effects associated with the use of different types  of

cocaine, it would be rational  to treat cocaine base offenses

more harshly for other reasons.  For example,  Congress could

rationally  seek to  strengthen the  deterrent effect  of the

narcotics laws  by  increasing the  "cost" to  a criminal  of

using or selling a cocaine substance that, like cocaine base,

is  sold  at  a   cheaper  unit  price  than   other  cocaine

substances.     Indeed,   of  the   four  citations   to  the

Congressional Record  that Singleterry offers in  his opening

brief  as  probative of  congressional intent,  each suggests

that  Congress  has been  concerned  that  the low  price  of

cocaine  base (in the absolute  sense as well  as relative to

cocaine) would lead to an explosion in drug use.

                             -18-
                              18

          In   any  event,   the  district   court  correctly

concluded that  "Congress  had before  it  sufficient .  .  .

information to  make distinctions  that would  justify .  . .

more  severe sentences  for trafficking  in or  using cocaine

base  or crack than cocaine itself."  Accord United States v.
                                                          

Frazier,  981 F.2d  92, 95  (3d Cir.  1992) (noting  that the
       

Third  Circuit,  "along with  every  other  federal court  of

appeals to rule on  the issue, has held that  the distinction

between cocaine  base and  cocaine in the  federal sentencing

scheme   is   constitutional  under   rational   basis  equal

protection  review"), cert.  denied,  113 S.  Ct. 1661,  1662
                                   

(1993).

     2.  Racially Discriminatory Classification
                                               

          Singleterry next argues that the  harsher penalties

for cocaine base  offenses are unconstitutional because  they

have such a disproportionate effect on blacks as to give rise

to an  inference that Congress and  the Sentencing Commission

established   those  penalties  for  the  purpose  of  racial

discrimination.  See Yick Wo v. Hopkins, 118 U.S. 356 (1886).
                                       

As  proof  of  disparate   impact,  Singleterry  offers  some

evidence that  (1) most  cocaine base  users are  black while

most users of cocaine are white, and (2) the vast majority of

sentences  for cocaine  base  offenses are  imposed on  black

defendants while white defendants comprise the largest  share

of  those  sentenced  for  cocaine offenses.    In  addition,

                             -19-
                              19

Singleterry   has   offered  some   evidence   that  Congress

anticipated  such an impact  because, in  adopting heightened

penalties  for cocaine  base offenses,  it was  attempting to

address a problem afflicting lower-income urban communities.

          We agree  that where  evidence of disparate  impact

leads  most  naturally  to  an  inference  of  discriminatory

purpose, the  governmental classification  may be  subject to

strict  scrutiny  under  equal  protection principles.    See
                                                             

McCleskey  v. Kemp,  481 U.S.  279, 293 (1987)  (holding that
                  

"`stark'" statistical pattern may serve "as the sole proof of

discriminatory  intent  under  the   Constitution")  (quoting

Village  of Arlington  Heights  v.  Metropolitan  Hous.  Dev.
                                                             

Corp., 429 U.S.  252, 266 (1977));  Washington v. Davis,  426
                                                       

U.S.  229, 242 (1976) ("[D]iscriminatory impact . . . may for

all   practical   purposes  demonstrate   unconstitutionality

because  in various circumstances  the discrimination is very

difficult to  explain on nonracial  grounds."); Gomillion  v.
                                                         

Lightfoot, 364 U.S.  339, 341  (1960); Yick Wo,  118 U.S.  at
                                              

373-74.    But  here,  as  we  suggested  in  discussing  the

rationality  of the  sentencing  scheme,  there are  racially

neutral grounds  for the classification that  more "plausibly

explain[]" its impact on blacks.  Personnel Adm'r v.  Feeney,
                                                            

442 U.S. 256, 275 (1979).  As a result, there is insufficient

evidence "that the distinction drawn between cocaine base and

cocaine was motivated by  any racial animus or discriminatory

                             -20-
                              20

intent  on  the part  of  either Congress  or  the Sentencing

Commission."  Frazier,  981 F.2d at 95 (citing  United States
                                                             

v. Simmons, 964 F.2d 763 (8th Cir.), cert. denied, 113 S. Ct.
                                                 

632 (1992), and United  States v. Galloway, 951 F.2d  64 (5th
                                          

Cir. 1992)).   But see United States  v. Clary, 846  F. Supp.
                                              

768  (E.D. Mo.  1994)  (holding  that sentencing  distinction

between  cocaine  base  and  cocaine  powder  violates  equal

protection principles after  finding circumstantial  evidence

of unconscious discriminatory purpose).   In short, there was

no  error  in  the  district court's  determination  to  this

effect.

          Finally, we note that while "[t]he equal protection

obligation  imposed by  the Due Process  Clause of  the Fifth

Amendment is not an obligation to provide the best governance

possible," Schweiker v. Wilson, 450 U.S. 221, 230 (1981), the
                              

absence  of a constitutional command  is not an invitation to

government   complacency.    Although   Singleterry  has  not

established  a   constitutional  violation,  he   has  raised

important questions  about the  efficacy and fairness  of our

current  sentencing policies  for offenses  involving cocaine

substances.   We leave the resolution of these matters to the

considered judgment  of those  with the proper  authority and

institutional capacity.

                             III.
                                 

                          CONCLUSION
                                    

                             -21-
                              21

          For  the foregoing reasons, we affirm Singleterry's

conviction as well as his sentence.

          So ordered.
                     

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                              22
