“…Many other variables are either missing or unavailable in the data-set, making it impractical or impossible to analyze attitudes and mental health conditions of offenders (Lewis et al, 2007;Goldberg, 2007;Haas & Killias, 2002;Sheley & Wright, 1995), gang membership (Decker et al, 1997;Thornberry et al, 2003;Watkins et al, 2008), differences between juvenile and adult offenders (Decker et al, 1997;Zawitz, 1995), differences between male and female offenders (NIJ, 2006), and offender-victim relationships (Heide & Petee, 2007;NIJ, 2006). Two primary factors that account for the large amount of missing values and insufficient data are lack of cases and difficulties in locating and obtaining information by the police.…”