PurposeThe purpose and approaches of this article differ from those of prior research in several ways. First, while existing leadership meta-analytic research has focused on the relationship between specific types of leadership and organizational correlates, this study is a comprehensive and systematic meta-study of overall leadership types and organizational effectiveness. Second, while most of the aforementioned previous leadership meta-analysis studies target various countries and organizations, this study focuses on the leadership of the police, especially the South Korean police, and organizational effectiveness. In particular, this study is necessary because leadership meta-analysis studies of police organizations are rare. Third, this study can contribute to the accumulation of leadership knowledge in the context of contingency theory. According to contingency theory, no form of leadership is effective in all situations. Both the environment and organizational factors of leadership have a significant impact on the effectiveness of leadership. In this regard, it is very meaningful to meta-analyze the studies on leadership and organizational effectiveness of the Korean police and interpret the results in conjunction with the Korean national context and the characteristics of the police.Design/methodology/approachIn this study, the authors conduct a meta-analysis of the studies on the leadership and organizational effectiveness of the South Korean police. To select the literature for the meta-analysis, the authors used the Preferred Items for Systematic Views and Meta-analysis procedure. First, 254 papers were searched, of which 133 were published in academic journals and 121 were dissertations. Second, 84 studies were selected, excluding 135 double-discovered studies, 30 studies unrelated to police leadership and 5 undisclosed studies. Finally, the authors checked the abstract and content of the literature. The authors evaluated the quality of the 36 studies that were selected through the above process. The authors estimate the sample size–weighted mean correlation by reflecting the sample size of each study in the converted Fisher's z-value. The final result is presented by reverting to the correlation coefficient for convenience of interpretation. Through this meta-analytic process, the authors estimated the mean effect size of whole leadership on the organizational effectiveness of the Korean police by integrating the effect size of each study.FindingsThe findings of this study have the following theoretical and practical implications. First, the results of this study indicate that the above trends in international leadership research have been applied to the Korean police as well and that the above trends in international leadership research have been applied equally to research into the South Korean police. The authors argue that more servant leadership studies are needed on the South Korean police. Second, the results of this study demonstrate that leadership is strongly correlated with organizational effectiveness among the South Korean police as well. Leadership is also found to be significantly positively related to attitude, behavior and satisfaction among the South Korean police. These results suggest that the leadership of police managers is very important for effective organizational management and improved police performance. Third, the results indicate significant differences in the effect sizes of each type of leadership. The largest effect size is the empowering leadership (EML), almost double the smallest effect size, authentic leadership. The results of the current study also indicate that transactional leadership (TSL) has a strong correlation with organizational effectiveness. Advanced research shows a significantly smaller effect than the magnitude of the effect size in this study. The authors examine the powerful effect of EML among the South Korean police from the perspective of organizational culture and the characteristics of the South Korean police. Influenced by social culture, the South Korean police also have hierarchical characteristics and a rigid organizational culture. In addition, although the police have strong discretion due to the nature of policing, individual police officers often have to take responsibility for the consequences of police discretion.Research limitations/implicationsThe most significant limitation of the current study is the lack of research using meta-analysis. The meta-analysis of the study was conducted on the police leadership and organizational effectiveness of one country, Korea. This is both a strong and weak point of the study. The lack of effect size on other leadership styles except transformational leadership and TSL can make it difficult to generalize the study results. There are only four samples of effect size, so careful interpretation is needed. This is also the inherent limitation of meta-analysis. After sufficient research is accumulated, it is necessary to re-estimate the effect size in future studies. In this study, the authors found differences in the effect sizes on organizational effectiveness by leadership types among the South Korean police, but more research is needed to determine the cause of the difference. In addition, this meta-analysis has a very high level of heterogeneity. This implies the possibility of various moderators, but the current study does not consider moderators. The authors recommend a continuous study on moderators that play a role in the relationship between police leadership and leadership outcomes.Practical implicationsIn this study, the authors found differences in the effect sizes on organizational effectiveness by leadership types among the South Korean police, but more research is needed to determine the cause of the difference. In addition, this meta-analysis has a very high level of heterogeneity. This implies the possibility of various moderators, but the current study does not consider moderators. The authors recommend a continuous study on moderators that play a role in the relationship between police leadership and leadership outcomes.Social implicationsThe authors’ empirical evidence once again supports the claim of leadership contingency theory that leadership is the result of the interaction of factors such as followers, leaders and organizational environments. It is difficult to conclude that the most effective leadership style among the South Korean police is EML. However, the authors’ findings can raise reasonable questions about generalized leadership effects and serve as evidence that the effects of leadership can vary across national and organizational contexts. Nevertheless, the authors can ask reasonable questions about the existence of generalized leadership effects. Furthermore, the authors’ findings can serve as evidence that the effectiveness of leadership can vary depending on cultural and organizational contexts.Originality/valueNumerous studies have been conducted on leadership and organizational effectiveness. However, meta-analysis studies on the relationship between leadership and organizational effectiveness focusing on certain national police forces have been limited. In this regard, the current study conducted a meta-analysis on the correlation between leadership and organizational effectiveness for South Korean police. While existing leadership meta-analytic research has focused on the relationship between specific types of leadership and organizational correlates, this study is a comprehensive and systematic meta-study of overall leadership types and organizational effectiveness. While most of the aforementioned previous leadership meta-analysis studies target various countries and organizations, this study focuses on the leadership of the police, especially the South Korean police, and organizational effectiveness. Previous research studies on the leadership of the Korean police have not properly considered national and cultural contexts. Most of them have the same limitations, that is, they applied each leadership theories that were developed in foreign countries (especially transformative leadership and transactional leadership) to the Korean police to explain whether each leadership type has a significant relationship with organizational effectiveness. The meta-analysis of this study can contribute to existing literature by overcoming this limitation. In addition, if the authors’ results match the cultural and historical characteristics of Korean police, they can provide evidence of the potential for effective police leadership in each country. The authors can also argue that meta-analysis of police leadership in other countries is necessary.
