Jean McGloin’s primary research focus is on groups and crime, which is reflected in several intersecting streams of work.  She has an ongoing research program focused on developing new theoretical explanations of peer influence, the role of peer network structure in shaping delinquency, and the extent to which individual characteristics condition peer influence.  She also conducts research on co-offending, including why offenders decide to commit crime with accomplices, under what conditions they will instigate group crime rather than follow others, and how co-offending networks can shape and influence the criminal career.  As part of this stream of research, she interested in how the group can shape and affect decisions about offending, both incentivizing and disincentivizing deviant action.  Finally, she also studies the role of gang membership in offenders' trajectories.