Based on the criminal law, the duty of police investigation is to get material fact; that is
the fact based on the true fact. Investigating officer needs some tactics and his own way to
recognize the identity of the suspected. One of the ways to get it is from fingerprint. It is really
needed because fingerprint can give the high accuracy level as long as not contaminate or not
broken from another things. Besides fingerprint, the information from the withers and the victim
is also needed in order to get authentication of the killing case. One of the traces of popular evil
is fingerprint of the doer. Sometimes he is not aware with that matter. The problems of this study
are what the obstacles that is faced by investigating officer in reveal the criminal act of killing.
The purpose of this study are to describe the effectiveness of fingerprint identifying the criminal
act of killing and to describe thew obstacles that is faced by investigating officer in reveal the
criminal act of killing. The approach of this research is using juridical sociology; studies that
analyze the problems that correlated with the law or doctrine legislation. The data of this study
are primary data and secondary data that are taken by using descriptive qualitative. It is used
because the results of the problems of the research describe the summary of the problems.
Therefore, the techniques of collecting the data are interview.