@article{discovery10194115, journal = {Global Crime}, publisher = {Informa UK Limited}, note = {This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives License (http://creativecommons.org/licenses/by-nc-nd/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited, and is not altered, transformed, or built upon in any way. The terms on which this article has been published allow the posting of the Accepted Manuscript in a repository by the author(s) or with their consent.}, month = {July}, title = {Exploring criminal specialisation in co-offending groups}, year = {2024}, keywords = {Co-offending; co-offending groups; bicliques; criminal specialisation; bipartite networks}, url = {http://dx.doi.org/10.1080/17440572.2024.2371326}, author = {Nieto, Alberto and Davies, Toby and Borrion, Herv{\'e}}, abstract = {Researchers have studied criminal specialisation at the offenders' level to understand criminal careers. Despite criminal careers comprising events in which offenders co-offend with others, we know less about the extent of co-offending groups showing signs of becoming specialists. To start addressing this gap, in this study we report a method through which we identified 1,796 co-offending groups in a network containing information about adult offenders (n = 76,697) connected to criminal investigations (m = 35,604) between 2010 and 2018. During this timeframe, one in five co-offending groups remained unchanged in their composition and re-offended. Of those re-offending, 54\% became specialists in crimes such as those affecting private property. The other 46\% that re-offended were generalists. Simulation analyses showed that the proportion of highly specialised groups was not observed by chance. These results suggest that criminal specialisation is a characteristic also shared by co-offending groups. Criminologists and practitioners might find helpful the method employed here to identify co-offending groups and assess their level of specialisation.} }