In this study, one case illustrates the regulatory psychological aptitude assessment, evaluation and interpretation of measurement tools. I extended the protocol by questionnaires matching to my research, which give a more comprehensive view of the factors caused by trauma. I found it interesting to prove closer how a member of the police, who defends public order, interprets and experiences the fact that he has violated the law this time. The man, who works for public safety, is in constant contact with people, meets their problems almost every day, helps citizens in difficult situations, behaves as an offender during off-time. I examined how he was able to bear the consequences of his actions responsibly and how he could cope with a traumatic experience. After experiencing the same situation in a different role, did he gain own experiences and due to them became his personality perceptible to change or rather he regressed to an earlier stage of development?