51 
be carefully watched and the right moment seized to go 
ahead. 
The interview .—This is always a test of wits, but the 
investigating officer has the whip hand, since the witness 
is usually playing a dangerous game which affects his 
calmness. Falsehood involves a frame-up. The neces¬ 
sary thing is to get behind the frame-up. The means by 
which this can be done is thorough questioning; perfunc¬ 
tory or aimless questioning will not do it. 
Unless the witness has previously made a statement or 
has refused to talk, it is usually best at first to let him tell 
his own story in his own way. If he is interrupted, he 
will begin to trim what he says accordingly. This state¬ 
ment should be signed and witnessed, as in any other 
interview, even though the investigator knows it to be a 
mass of falsehoods. 
Then commence to question. In most cases inter¬ 
rogation should begin at a point a considerable time 
previous to the offense, and lead step by step in minute 
detail through it. The frame-up of a false case practically 
always revolves around an attempt to establish an alibi, 
and the easiest way to break this down is to question 
minutely about details—how long together, how seated, 
what said, order in which things occurred, etc. When 
the alibi is true except as to date, get outside of it by con¬ 
necting with dates some distance from the ones in question. 
As soon as you reach a point not contemplated in the 
frame-up, contradiction will begin, which gives the officer 
a lead. In case a witness refuses to talk, show him that 
you have something on him. This will almost always 
start him to explaining; then it is comparatively easy to 
keep him going. When sure enough of your ground, you 
can begin to jump him directly with what you know to 
be false. Do not ask him if he did thus and so, but say: 
“You say you did thus and so?” and make him say yes; 
then, “I know better—you did thus ahd so.” Make it 
clear that he can not string you; not by asserting it, but 
by demonstration. With some types of men, however, 
ground can be gained by even more severity; that is, 
“What do you mean by lying to me?” 
