According to the current legal system in Taiwan, sex offenders must enter a community intervention program after being released from prison. However, recent research of sex offenders has suggested that over the longer term after offenders are released, they have a high rate of sexual re-offense. This shows that the daily struggles while returning to society might contribute to sexual re-offense in different ways, so as to impact the risk factor of sexual re-offense. Thus, assessing the re-offense attempts of sex offenders in the community intervention program is worthy of attention in clinical practice. However, considering the importance of monitoring linguistic behaviors, there is very little existing research that has empirically documented the language use of sex offenders and how that may impact recidivism of sexual offense. Therefore, the aim of this case report attempts to explore how sex offenders' state of minds are reflected in daily language use and how linguistic markers and sexual re-offense may be related.
　　Pennebaker and his colleagues have provided excellent reviews of the psychological aspect in language use. They believe that either expressive writing or spoken language demonstrate cognitive reflective models. Instead of focusing on "what" is said by the individuals, paying attention to "how" the individuals say it is much more crucial. Furthermore, it opened a window for researchers to analyze the psychological vulnerabilities or risks of sex offenders as well as having further understanding of the underlining altered state of mind that is intertwined with the surroundings. Considering these concerns, this case study involved a biweekly log written by an ex-sex offender in a community intervention program. The time frame for the study lasted nearly one year until the reoffense occurred. A total of twenty-one free-writing diaries were analyzed with a computerized text analysis software, Linguistic Inquiry and Word Count (LIWC). Beyond examining several categories of words with psychological meanings, such as negative and positive affect, this case study also applies higher-order algorithms based on LIWC dictionaries, including the index of complex thinking, the index of honesty, and the index of social-emotional style.
　　Considering months as the analysis unit, the one-year period is divided into the initial stage (April to July), incubation stage (August to December) and action stage (January to March). The results suggested that the language style could possibly indicate signs of recidivism for sex offenders over the long-term while recording their thoughts. The language used during the action stage demonstrated four valuable language shifts compared to other stages. First, the total number of words continually decreased over time. Second, positive affect words decreased and negative affect words increased. Third, the index of complex thinking decreased. Fourth, the index of honesty rose with a V-shape. This result is aligned with the inference of the deception theory of Ekman, Vrij, and DePaulo.
　　To conclude, the study may be of importance in explaining language with psychological meaning that could reflect subtle changes in hidden intention of crimes. In addition, the findings of the study also have implications for observing signs of deception and the subsequent re-offense from the written text. Thus, language analysis is proving to be a useful source for conducting psychological evaluation and risk management for sex offenders who under treatment. That said, the generalization of the results to other populations with different backgrounds may be limited, so more research is called for to expand the understanding of the language style of sex offenders.