2 
Expert  Testimony. 
(  Am.  Jour.  Pharm. 
1     January,  1905. 
questions.  Undoubtedly  these  impersonal  elements  are  important 
factors;  but  it  must  be  admitted  that  there  are  also  personal  factors, 
and  that  for  the  latter,  physicians  and  chemists  are  not  without 
blame.  When  men  ,  of  equal  reputation  and  competence  can  be 
found,  apparently  in  any  desired  number,  to  form  either  of  two 
opposite  opinions  upon  the  same  apparently  simple  set  of  facts ;  can 
be  induced  to  express  positive  and  conflicting  views  upon  questions 
concerning  which  the  evidence  is  insufficient  for  the  formation  of  a 
positive  view  of  any  kind ;  and  are  willing,  moreover,  to  suggest  to 
an  attorney  questions  that  seem  to  have  no  other  purpose  than  to 
confuse  scientific  colleagues  who  may  appear  as  witnesses  on  the 
other  side,  or  unfairly  to  impugn  and  belittle  the  evidence  given  by 
such  colleagues — is  the  assumption  wholly  without  plausibility  that 
the  nature  of  the  testimony  given  by  any  expert  witness  is  in  effect 
determined  by  the  necessities  of  that  side  of  the  case  upon  which  he 
is  employed  ?  We  know,  and  many  attorneys  know,  that,  despite  its 
plausibility,  the  assumption  is  far  from  being  correct.  But  that  is 
because  we  and  the  attorneys  know  what  the  newspapers  and  the 
public  do  not  know  and  cannot  know ;  namely,  how  often  physicians 
.and  chemists  decline  to  testify  in  behalf  of  interests  that  have  con- 
sulted them,  because  on  examination  of  the  facts  they  find  that  they 
cannot  truthfully  give  the  testimony  desired.  That  incompetent, 
inaccurate,  overzealous,  or  even  untruthful  persons  sometimes  appear 
■via  <the  role  of  expert  witnesses,  playing  it  very  much  to  the  satisfac- 
tion not  only  of  their  employers,  but  also  of  the  jury  and  the  specta- 
tors— may  be  admitted.  With  this  phase  of  the  subject,  however, 
I  do  not  purpose  to  deal  at  this  time.  I  shall  consider  only  the 
difficulties  besetting  competent  men,  desirous  to  tell  the  truth  and 
nothing  but  the  truth,  when  they  go  upon  the  witness  stand  to  in- 
struct courts  and  juries  upon  pharmacologic  and  toxicologic  questions. 
In  the  first  place,  it  is  often  requisite  to  state  technical  facts  in 
cimtechnical  language.  There  is  much  difference  between  lack  of 
technicality  and  simplicity.  The  simplest  statement  is  always  the 
foest;  but  the  untechnical  statement  is  not  always  the  simplest — fre- 
quently it  is  the  most  complex.  Consider  for  a  moment  only  the 
physical  and  chemical  questions  of  osmosis,  of  atomic  weight,  of 
^valency,  of  crystallization,  of  stereochemism,  of  ionization  ;  or  the 
pharmacologic  questions  of  the  effects  of  drugs  upon  metabolism 
<or  upon  cell  structure.    How  can  such  matters  be  expressed  in  other 
