We investigate whether autistic people’s vulnerability is taken into account at each stage of the criminal justice system (CJS). Defence lawyers from twelve nations were included in the study although the sample was predominantly from the UK. Lawyers completed an online survey regarding one case in which they had defended an autistic client between January 2015 - January 2020; and on one case in which they had defended a non-autistic client charged with a similar offence, to provide a comparison group. Ninety-three lawyers (85% in the UK) reported on one autistic case, and 53 also reported on one non-autistic case. 75% of autistic clients were not given reasonable adjustments during the process. Only 43% were offered an appropriate adult during police investigations, even though they had an existing diagnosis of autism. 59% of prosecution barristers and 46% of judges said or did something during the trial that made the lawyers concerned that they did not have an adequate understanding of autism. Lawyers were 7.58 times more likely to be concerned about their autistic client’s effective participation in court and were 3.83 times more likely to be concerned that their autistic clients would engage in self-harm, compared with their non-autistic clients. There is a failure to identify and address autistic peoples’ disability within the CJS. There is a need for mandatory autism training for police officers and the judiciary, with a focus on identifying autism and understanding the needs of autistic people so that reasonable adjustments are offered in all cases.