32 
Expert  Testimony. 
(  Am.  Jour.  Pharos 
I    February,  1905. 
the  accused  person.  If  the  public  prosecutor  nevertheless  proceeds 
to  trial,  being  satisfied  upon  other  grounds  that  such  is  his  duty, 
and  fails  to  call  the  chemist  or  pathologist  who  has  made  the  nega- 
tive finding,  is  it  the  latter's  duty  to  volunteer  his  evidence  ?  The 
answer  to  that  question  is  beyond  the  scope  of  this  paper,  but, 
nevertheless,  the  question  needs  to  be  stated. 
SUMMARY  OF  CONCLUSIONS. 
(1)  The  difficulties  attending  expert  evidence  upon  pharmaco- 
logic questions  could  be  in  large  part  obviated  (a)  by  adopting  the 
principle  of  controlled  examinations  with  preservation  of  portions  of 
materials  examined  and  exhibition  of  material  results ;  (f)  by  sub- 
mitting  scientific  questions  to  the  judgment  of  a  jury  or  commis- 
sion of  experts  who  should  hear  the  relevant  testimony  in  the  pres- 
ence of  both  parties  and  their  counsel,  and  report  to  the  court,  and 
whose  unanimous  report  or  discrepant  reports  should  be  submitted 
to  the  trial  jury  as  part  of  the  evidence  in  the  case.  Before  such  a 
commission  scientific  experts  might  be  allowed  to  appear  frankly  as 
advocates  arguing  upon  evidence  submitted,  but  no  mere  opinions 
should  be  given  as  evidence  ;  it  being  the  function  of  the  commis- 
sion to  formulate  opinions  for  the  guidance  of  the  court  having 
final  decision  of  the  case. 
(2)  As  the  plan  suggested  in  the  foregoing  paragraph  is  not 
likely  to  be  adopted  for  many  years,  if  ever,  the  duty  devolves  upon 
physicians  and  pharmacists  called  as  expert  witnesses  under  the 
present  system  to  guard  their  own  actions  and  evidence  so  that  the 
reproach  of  partisanship  and  venal  interest  which  now,  justly  or 
unjustly,  attaches  to  the  testimony  of  experts  upon  pharmacologic 
questions  may  be  removed  from  the  honest  and  competent  majority 
and  a  sharp  line  of  distinction  be  manifest  between  them  and 
others. 
(3)  The  chief  difficulties  that  honest,  sincere  and  competent  ex- 
pert witnesses  have  to  meet  are  of  four  orders  : 
(a)  The  necessity  to  state  technical  matters  in  untechnical  terms. 
There  is  no  way  of  avoiding  this  and  the  expert  can  only  meet  it 
as  best  he  may,  deliberately  using  technical  terms  when  necessary 
to  make  the  record  complete,  and  afterward  explaining  them  as  welL 
as  possible  in  untechnical  language. 
(b)  The  combination  of  witness  and  advocate  in  the  same  person. 
