In any criminal justice system ‘police’ plays a very pivotal role. Their role in rendering ‘justice’ in any criminal cases cannot be undermined. Right from investigation to establishing the guilt of the accused in the criminal trial, police plays a very crucial role. Through this article an attempt is made to discuss the challenges that the police has to face during the investigation and trial of criminal case. The article also attempts to discuss the manner in which the police can work with other agencies so as to improve the criminal justice system as a whole. We know that in Indian Criminal Justice system there are three major agencies that are involved in resolving the crime and providing the justice viz police, prosecution and lastly judiciary. Amongst these three important agencies, the role of police is very important in rendering justice in criminal cases. The role of police agency has a magnitude that affects the operations of the whole criminal justice system. It is police who is first in line to make contact with the victims, the witnesses and the accused. It is accepted fact the police play a crucial role during the course of investigation, identification of accused and establishment of guilt of the accused in the criminal case. It is humbly submitted that Indian Criminal Justice System (more specifically criminal investigation) works mostly for the benefit of the rich people who are often politically, economically and socially powerful, and not for the innocent victim. Through this article an attempt will be made to touch upon some of the existing abnormalities in the Indian Criminal Justice System, the challenges that the police have to face during the whole criminal investigation and the ways in which the police can work with other agencies (especially the judiciary), to improve upon the overall efficiency of the criminal justice system.