Purpose
Ethical leadership is at the forefront of what matters in today’s business life and current issues, with a view to making strong moral decisions through bilateral communication. Service innovation behavior is important in terms of individual and institutional actions in the process of producing and implementing new ideas. Investigating the mediating role of psychological capital which consists of self-efficacy, optimism, hope and psychological endurance dimensions, between ethical leadership and service innovation behavior, is a matter to be investigated. This study aims to assess the impact of ethical leadership on service innovation behavior by means of a comprehensive literature review. In this framework, psychological capital forms the scope of researching the mediating role.

Design/methodology/approach
This study was conducted with 376 blue-collar workers randomly selected from 140 company which were selected from 1,294 joint stock companies among 76,882 companies operating in the province of Adana in Turkey and registered in the Adana Chamber of Commerce, by applying a questionnaire of 40 items.

Findings
As a result of the factor analysis, 6 items which could not provide reliability were extracted from the scale and the remaining 34 items were distributed in three factors and the validity of the construct validity was measured by the convergence and divergence methods. Construct reliability (CR) values were found to be statistically significant (SRMR: 0.50, RMSEA = 0.058, IFI: 0.955, CFI = 0.97, GFI = 0.96, AGFI = 0.86, TLI = 0.97, χ2/s.d. = 2.264) when it was above 0.7, and the structural equation model determined that the research data and the initially determined model are compatible. Ethical leadership has a significant effect on psychological capital (ß = 0.224, p < 0.001), ethical leadership has a significant effect on innovation (ß = 0.113, p < 0.001), psychological capital was found to have a significant influence on service innovation (ß = 0.965, p < 0.001), and ethical leadership was mediated by psychological capital on service innovation behavior (SIE = 0.235).

Research limitations/implications
Further research is needed to assess conducting research in enterprises with different cultural characteristics. This paper provides the effectiveness of ethical leadership and psychological capital factors, which are effective in improving employee service innovation behavior and enabling managers to develop human resources strategies in this respect.

Practical implications
The results provide the impact of ethical leadership on the productivity of employees in the workplace and provide practical benefits in terms of developing innovation-oriented service development behaviors.

Social implications
The innovative behaviors of the employees enable the development of innovative ideas in social life by contributing to consumer satisfaction and economy. Ethical leadership ensures positive behaviors in the society by ensuring that employees in the workplace develop justice sentiments.

Originality/value
The mediating role of psychological capital between ethical leadership and service innovation behavior has not been investigated before. In this study, the effects of self-efficacy, optimism, hope and resilience factors were investigated in providing ethical leaders and employees, creating value in the enterprise, and in providing innovation-focused services for employees.