1. Introduction
In the rapidly changing modern business environment, organizations constantly seek to resolve the puzzle of the emergence of creativity to survive and grow [
1,
2]. To achieve goals, firms have invested significant funds to develop the creative abilities of their members because they are the main actors who substantially plan and perform innovation [
3,
4,
5]. In line with this, scholars and practitioners have tried to identify various antecedents of creativity, including member characteristics and organizational contexts [
6,
7,
8].
Among the preceding factors, this paper focuses on leadership by relying on the suggestion of previous works that leadership greatly influences members’ creative group processes [
6,
8,
9,
10]. More specifically, considering the critical impacts of corporate ethics [
11], we investigate the influence of ethical leadership. An ethical leader both performs personal moral behaviors and builds social relationships to facilitate ethical conduct among employees [
12]. Works on ethical leadership have demonstrated that this leadership style helps enhance the quality of employee perception, attitudes, behaviors, and group-level outcomes [
13,
14,
15].
Although many studies have examined the relationship between ethical leadership and creativity [
15,
16,
17,
18,
19,
20], research gaps remain to be addressed [
21]. First, works on the ethical leadership–creativity link have reported inconclusive results in association. In other words, some studies have demonstrated that ethical leadership increases the level of creativity, but other works have indicated that the leadership was not related to creativity [
15,
18,
19,
20] and even decreased creativity [
16,
17]. For example, Feng and his colleagues [
16] demonstrated a curvilinear relationship between ethical leadership and employee creativity to indicate that employee creativity improved as ethical leadership increased from low to moderate levels, but the employee creativity improvement was attenuated when ethical leadership increased from moderate to high levels. Similarly, Mo and Ling [
17] questioned that team creativity might be overwhelmed by the zenith quantity of ethical leadership. Considering that the inconclusive issue may be originated in the lack of studies on the underlying mechanisms (e.g., mediators, moderators) in the link, empirical works investigating how and when ethical leadership influences creativity are highly needed.
Second, previous works on the ethical leadership–creativity link have mainly focused on employees’ individual-level creativity. Although we acknowledge that employee creativity is the basis of the collective-level creativity of innovation, group- or collective-level creativity is more likely to be directly associated with various organizational outcomes [
6,
8,
9,
10]. Thus, we suggest that works that examine the influence of ethical leadership on collective-level creativity are required.
Third and most importantly, extant work on ethical leadership has underexplored the close association with other leadership styles [
21]. Considering that a leader is likely to use various kinds of leadership styles simultaneously, as well as that leadership styles tend to overlap from the theoretical and empirical perspectives [
22,
23], scholars need to investigate the role of other styles of leadership in explaining the influence of ethical leadership. In line with the suggestion of previous work that leadership is likely to create a creative group process of members [
6,
8,
9,
10], attempts to consider leadership styles as an intermediating mechanism in the ethical leadership–creativity link are required.
To address the issues described above, in this paper, we investigate the mediating role of team-level shared leadership in team-level ethical leadership and team creativity. In addition, we delve into contingent and contextual factors that explain the influence of ethical leadership on share leadership.
Multisource leadership highlights the importance of shared leadership as a “dynamic and interactive influence process” [
24]. The emergence of a series of formal and informal leaders [
25] offers an outlet for organizations to overturn the obstacle on sustainability [
26]. Increasingly, scholars have addressed the superiority of shared leadership because its influences stem from team members. Research has shown positive work outcomes such as innovation [
27,
28], involvement [
24,
27,
28], extra-role behavior [
29,
30], and even team-level creativity and performance [
31,
32]. Based on the role-making perspective [
33], we propose that ethical leadership may enhance the level of shared leadership, so increased shared leadership would boost the degree of creativity members and teams [
27,
28,
34].
We also suggest that the influence of ethical leadership on shared leadership may be moderated by the group level of dispersion of the leader–member exchange (LMXD), which may influence the leadership effectiveness. Despite abundant evidence for the benefits of high-quality LMX [
35], LMXD as a group-level construct shows deleterious effects on the group dynamic and explains when and how leaders’ development has attenuated or even invalidated employees. Scholars have pointed out that it is important to figure out the moderating role of this dispersion or differentiation that produces adverse outcomes [
36,
37].
To explore the catalytic agent mechanism of shared leadership, our research examines the mediating effect of shared leadership in the ethical leadership–creativity link. Moreover, this study suggests that an important contingent factor (i.e., moderator) may expand the relationship between ethical leadership and shared leadership in an elaborate manner. In addition, this study will offer empirical findings to address confusion in the leadership and creativity literature through the team-level moderated mediation model. This paper may contribute to ethical leadership literature as follows. First, we try to resolve the inclusive results in the ethical leadership–creativity link by investigating the mediating effect of shared leadership and the moderating effect of LMXD. Second, this paper examines the influence of ethical leadership on collective-level creativity based on the argument that group- or collective-level creativity is more closely associated with various organizational outcomes [
6,
8,
9,
10]. Third and most important, this paper considers the shared leadership style as an intermediating mechanism (i.e., mediator) in explaining the influence of ethical leadership on team-level creativity.
5. Discussion
5.1. Theoretical Implications
The goals of this study are ambitious in seeking to add understanding to several recent studies. First, we are attending to the team construct with the effectiveness of leadership. Even though the topic of ethical leadership and creativity has been getting attention for many years, our study developed an innovative mechanism and offered an alternative explanation for how and when ethical leadership contributes to creativity. This study may offer an example of the solution to extend the boundaries of ethical leadership [
84]. We think about the role the leader wants to promote or train the employee to play, which is the key facet of ethical leadership.
When focusing on shared leadership development, from what we know, this is the most advanced study that has presented vertical ethical leadership with shared leadership at a horizontal model with the conditional effect. Our study integrated ethical leadership with shared leadership based on role theory and the SIP perspective. The findings suggested that vertical ethical leadership as an antecedent condition can stimulate shared leadership in a team. We also added the interaction effect on this influence to see when ethical leadership best stimulates shared leadership, thereby exacerbating the evidence in the statement of that vertical and shared leadership are auxiliary and complementary [
30,
34,
49]. Moreover, because studies have investigated that shared leadership positively related to creativity, this study was consistent with the literature, but we additionally offered direct and indirect paths from shared leadership to team creativity.
Third, the results also extend our understanding of the literature on creativity. This study demonstrated leadership as the driving force for team creativity and that shared leadership showed a powerful mediating effect on the mechanism through ethical leadership to creativity by interplaying two leadership properties in emerging creativity. Ethical leadership contributed directly and indirectly to team creativity, while shared leadership contributed more directly than ethical leadership. With these results, we provided a case and explanation on integrating and developing leadership to sustain team innovation most effectively.
Finally, this study proposed LMXD as a team contingency factor that can diminish ethical leadership’s effects on shared leadership and, consequently, creativity. The finding on the moderating effect of LMXD is beyond expectation. By following the command that research should embrace the perspective that simultaneously considers the paradox of LMXD [
36,
85], this study provided an interesting team-level case to discuss the phenomenon that the impact LMXD’s interaction with ethical leadership has on shared leadership will be mitigated by high LMXD because of the perception of inequality under allocation preferences theory [
71]. Moreover, shared leadership demonstrated the ability to digest and endure differentiation and diversity in the team environment, which was proposed previously [
59].
5.2. Practical Implications
Accordingly, this study makes several contributions to practitioners. First, team leaders should avoid unethical behavior. We believe the concerns regarding ethical leadership will continue for several generations. Leaders and managers should involve themselves in ethical leadership behavior as early as possible. Through ethical efforts, team creativity will be developed, and the higher level suggests that positive organizational outcomes could be near at hand. What is more, ethical leadership creates equality in the organizational environment by setting role models and sharing common goals, which makes a platform upon which leadership can adapt to changing times.
Second, we suggest that team leaders encourage and empower supervisors to take the role of leadership adaptively. It is critical to set the foundation that ethical leaders leading their followers feel trusted and involved, then members may participate in decision making and have more opportunity to exercise leadership. Ethical leadership could contribute to cultivating members in the role taking-making process. Once a member takes the role and makes a role under a moral model and shared goals, optimistic individuals and team performance can be expected.
However, the evolution and sustainable development of shared leadership requires vertical leadership [
34]. Scholars argued that vertical leadership should consider the different leadership resources [
52], such as external stakeholders and how to integrate resources. Typically, the way to coordinate internal and external resources is the message for leaders.
Fourth, team leaders should think about ensuring that a suitable balance is maintained in their workplace relationship. The exchange between leaders and members is a dynamic across-level complex process [
69]. As suggested by scholars [
36], depending on the situation of perspective or behavior, the differentiation in LMXD can judge supposition or devastation. Team leaders may increase the targeted training or particularly encourage and reward behavior for excellent members after observing that shared leadership is working in a team. Similarly, scholars suggested that shared leadership will be an alternative solution to assess talented leader candidates [
26]. Therefore, both ethical and shared leadership are priority matters for human resource development.
Moreover, rethinking the different results regarding leadership with creativity, we advise leaders to stand on the same front with their members to reduce the conflict perspective. Leaders and members may hold different minds on equality and equity treatment. More seriously, the dilemma is that leaders should judge quality and quantity creative performance accurately. We believe that it is more than just making a simple choice from a group. Instead, the key to the solution is how leaders can transform diversity into a positive force. We further suggest the leader eliminate obstacles preventing members and the team from breaking the boundaries toward a harmonious and inclusive work environment.
5.3. Limitations and Suggestions for Future Studies
We identified and discussed the limitations of this study as follows. First, the limited sample size of our study may result in bias. Even though the sample quality is high and targeted for the research subject, the disadvantage of small samples should be addressed. Even if the study thoroughly tested samples and assumptions using SmartPLS [
72] and PROCESS Macro [
73], there might be a better explanation for the relationship between leadership and creativity if more samples and cases were obtained for multi-level or cross-level analysis.
There is another limitation regarding respondent identification. HRD Korea, as a public institute, highlights its advantages in leadership development, but compared with service work, innovation and knowledge work are less critical in perspective. Third, multisource and multiple-time data collected can effectually evade the risk of CMB. This study adopted multisource data but not time waves data collection, which lacks attention to the CMB issue.
Fourth, because we were interested in examining the mechanism between vertical ethical and shared leadership, this study adopted a self-reported scale, which checked if shared leadership was sparked by ethical leaders from the angle of team members’ view. Some scholars remarked that the network approach for operationalization measurement more accurately explains the team-level leadership concept [
30]. In this way, we suggest that future studies consider that shared leadership’s social networks change over time. A similar potential limitation is the operationalization of LMXD. Even though the statistical indices were preferred by scholars [
75], the process measurement of LMXD may be controversial. In addition, we have identified the impact of LMX on shared leadership and recommend future research digging into LMX and shared leadership mechanisms.
Furthermore, while thinking about the mediating effects of shared leadership, we suggest that future research consider other constructs that highly correlate to shared leadership as control variables to ensure the accuracy of variance and results. Moreover, we noticed that diversity as a latent factor may lead to future vertical and shared leadership relationships research. This study has advanced this by acknowledging that the relationship difference influences the ethical leadership effect. However, team creativity is relatively stable due to leveraging shared leadership, even in the case of different LMXD situations. While our findings help clarify the contradictions in the leader–member exchange, the heterogeneity of the result of LMXD remains to be investigated. Therefore, this study further commands researchers to draw upon allocation preferences theory [
71] and other related approaches to assess the influence of diversity and differentiation on vertical and shared leadership interaction.
6. Conclusions
Team creativity is the top priority of leaders for team development. With the changing times and organizational development, research increasingly provides evidence on leadership effectiveness and creativity. For instance, scholars have suggested cultivating team creativity facing diversity. They offered the advantage of inclusive leadership [
86], which fully encourages team members to participate and empowers team members to join the work process. Alternatively, shared leadership [
62,
87] distributes the “leader” position to team members and aims to make full use of employees’ talents and actively mobilize the enthusiasm of employees. In addition, the personality traits of leaders, namely, humble [
88], narcissistic [
89], abusive [
90], and open [
91], have also attracted wide attention from scholars.
From the recent research, it is not difficult to find that leadership remains a pivotal link to team creativity. How to promote rather than weaken creativity, combined with the context to judge the right leadership style, has become the focus of scholars. This study is consistent with the research focus mentioned above. We also take shared leadership as our entry point, providing a new perspective for understanding the relationship between well-known ethical leadership and team creativity. The results of this paper suggest that team leaders trying to create conditions where team members participate in shared leadership should consider LMXD patterns, as these may affect team creativity.