Police officers usually start the charging process with an arrest or citation. They then send copies of their reports to a prosecutor's office staffed by government lawyers whose job it is to initiate and prosecute criminal cases. Prosecutors can look at all the circumstances of a case, including the suspect's past criminal record. They can file charges on all crimes for which the police arrested a suspect, can file charges that are more or less severe than the charges leveled by the police, or can decide to not file any charges at all. For suspects who are in custody, speedy trial laws typically require prosecutors to file charges, if at all, within 72 hours of arrest.
Some jurisdictions require prosecutors to charge a suspect even sooner.
For example, California requires that charges be filed within 48 hours. Penal Code Sec. However, prosecutors' initial charging decisions are subject to change. For example, a prosecutor's final decision on charges may not be determined until after a preliminary hearing, which may take place more than a month after arrest. Arrest reports summarize the events leading up to arrests and provide numerous other details, such as dates, time, location, weather conditions and witnesses' names and addresses if that information is available.