AFebrrry!?9aor5m-}  Expert  Testimony.  81 
THE  PROPER  SCOPE  OF  SCIENTIFIC  (SO-CALLED  EX- 
PERT) TESTIMONY  IN  TRIALS  INVOLVING  PHAR- 
MACOLOGIC QUESTIONS.1 
By  Solomon  Sows  Cohen,  M.D.,  of  Philadelphia, 
Professor  of  Clinical  Medicine  in  Jefferson  Medical  College. 
{Continued from  p.  ij.) 
(6)  That  one  must  be  expected  to  answer  frankly  all  questions  by 
opposing  counsel,  without  reservation  or  evasion,  regardless  of  the 
effect  of  such  answers  upon  the  theory  of  either  side. 
(7)  That  one  is  not  to  be  asked  irrelevant  questions,  for  the  pur- 
pose of  consuming  time  or  raising  clouds  of  dust;  or  to  be  asked  to 
make  captious  criticisms  of  the  testimony  or  methods  of  others ;  or 
in  any  way  to  be  made  a  party  to  methods  of  presentation  of  facts 
and  opinions,  which,  however  admirable  from  the  viewpoint  of  an 
attorney's  efforts  to  serve  his  client,  are  opposed  to  the  spirit  ot 
truth-seeking  science. 
It  is  not  to  be  expected  that  one  can  alter  the  badgering,  hector- 
ing, and  efforts  at  confusion  which  present  juridical  standards  per- 
mit and  even  applaud  in  cross-examination.  But  one  can  at  least 
refuse  to  supply  ammunition  for  such  practices,  to  support  them,  or 
to  countenance  them. 
A  more  difficult  ethical  question  than  we  have  yet  considered  is 
that  presented  to  a  chemist  who  has  been  called  upon  to  make  an 
analysis  of  suspected  substances,  when  his  analysis  reveals  the  pres- 
ence of  that  which  the  attorney  consulting  him  wishes  absent,  or 
vice  versa.  Is  he  to  insist  upon  being  called  as  a  witness  ?  It  is  no 
longer  a  question  of  testifying—for  the  attorney  will  not  wish  him 
to  do  so — but  of  not  testifying.  An  analogous  question  is  some- 
times presented  to  pathologists.  How  shall  it  be  decided  ?  Sup- 
pose a  chemist  or  a  pathologist  has  been  asked  to  examine  the  tis- 
sues of  a  person  suspected  to  have  been  poisoned,  for  evidence  of 
the  poison  or  its  effects  ?  He  fails  to  find  such  evidence.  This  is 
not  a  mere  matter  of  opinion,  but  of  fact.  Or,  take  a  somewhat 
simpler  case :  suppose  a  chemist  is  asked  to  examine  suspected 
powders  or  liquids  or  foodstuffs  for  the  presence  of  poison  and  fails 
to  find  it  ?    It  is  possible  that  his  negative  testimony  might  help 
1  An  address  delivered  before  the  Philadelphia  College  of  Pharmacy,  Novem- 
ber 15,  1904. 
