This is especially true when organized constituencies of crime victims exist. A prosecutor deciding whether to file a spousal assault charge, or whether to file it as a misdemeanor or a felony, is likely to consider the reactions both of the group and of the individual victim. Occasionally a prosecutor will decide that a basically good person made a stupid mistake that shouldn't result in a consequence as severe as a criminal charge. If a felony is involved, prosecutors sometimes leave it to grand juries to make the charging decisions. However, unlike petit juries, which only sit on one case, grand juries involve a time commitment typically lasting between 6 and 18 months, and the grand jurors may, in the course of their service, address many cases.
Grand juries meet in secret proceedings.
Petit juries serve during public trials. By contrast, a petit jury usually consists of between 6 and 12 people. Petit juries generally have to be unanimous to convict a defendant. Grand juries need not be unanimous to indict. In the federal system, for example, an indictment may be returned if 12 or more jurors agree to indict.