Vulnerable individuals frequently come into contact with the criminal justice system with those with mental health disorders over-represented in custody. Therefore, it is crucial to identify vulnerability in order to ensure the appropriate safeguards can be put in place. Research has documented that this is problematic and can be influenced by a number of factors. The current study, therefore, aimed to understand how custody officers in England and Wales made sense of different types of information presented to them, the impact that it had on their initial disposal option and whether there was a difference in police force area. Six case scenario vignettes containing different types of vulnerability were developed and disseminated. A total of 237 custody officers from 25 police forces participated. Results highlighted that custody officers were more likely to obtain a mental health assessment in all case scenarios, except if the individual displayed comprehension difficulties – custody officers would instead seek to implement the services of an Appropriate Adult. In addition, differences between police force areas were observed. Police forces in the North of England were the least likely to obtain the assistance of an Appropriate Adult when presented with a vulnerable suspect compared to other police force areas. This suggests fundamental differences in the disposal options preferred between police force areas and has implications for the treatment of vulnerable individuals in police custody.