Criminal investigators have numerous responsibilities when conducting investigations such as following certain procedures and overcoming obstacles to obtain crucial evidence. Jackall describes how officers are required to write a report and research a case. However, Jackall described that in officer Tebbens" situation in researching a quadruple homicide acquiring evidence took extensive time and effort. Officer Tebbens was only given bits and pieces of evidence, an alias, and a few witnesses who were jumbled and confused about their recollection of the event. In criminal violence cases few people actually witness them and often as in Tebbens"case the witnesses have long criminal records and their reliability is questioned. A second responsibility criminal investigators must maintain is enforcing the law and bringing criminals to justice. It is difficult to enforce laws created by the justice system on criminal's who have produced a peculiar idea of another social world with separate laws for them to follow. For example, drug dealers see dealing drugs as a profession and a tool of the trade. Although, criminal investigators are expected to find criminals and arrest them it is difficult to find a criminal who doesn't exist. Officer Tebbens also faced this obstacle in his investigation because, witnesses new only the alias of one of the shooters but, the shooter did not have a criminal record and Tebbens had no way to track him. Another responsibility criminal investigators must complete is arresting and convicting the criminal. Despite the criminal activity of an individual investigators struggle with the difficulty of completing this task. Officers express that it is tough to prosecute a criminal because, the judicial system has established a separate set of rules and "Whatever substantive justice, as defined by some standard, that is achieved in the criminal justice system is the product of sustained effort by men and women in the system who decide to make the system work toward a certain end.