When you picture a bad boss, you’d probably think of someone who’s perpetually harsh, demanding, or downright abusive. Meanwhile, good bosses tend to be supportive and involved. But what if your boss oscillates between being supportive one day and abusive the next?

According to a new study published in the Journal of Applied Psychology, this unpredictability — what researchers are calling “Jekyll-and-Hyde leadership” — can be even more damaging to employees than a consistently abusive boss.

“We already know that abusive leadership takes a serious toll on workers — but now we’re seeing that leaders who swing back and forth between abusive and ethical leadership do even more damage to employees,” says Dr. Haoying Xu, the study’s lead author and an assistant professor of management in the Stevens School of Business. “It turns out that reverting to an ethical leadership style doesn’t magically erase the impact of prior bad behavior — and in some circumstances, it can actually make things worse.”

Good cop bad cop

The study involved surveys and field experiments with over 650 full-time employees across the United States and Europe. Basically, Dr. Haoying Xu and colleagues wanted to see if bosses who swing from abusive to supportive are actually helping employees.

The findings were clear: while consistent abuse is harmful, an on-and-off pattern of ethical and abusive behavior creates even more uncertainty, ultimately causing greater damage to employees’ wellbeing.

Xu explains that the uncertainty of not knowing which version of the boss will show up — whether it’s the supportive mentor or the ruthless critic — leaves employees constantly on edge. This unpredictability creates a toxic work environment where employees are forced to walk on eggshells, never knowing if their efforts will be appreciated or harshly criticized.

“If you’re constantly guessing which boss will turn up — the good cop or the bad cop — then you wind up emotionally exhausted, demoralized, and unable to work to your full potential,” Dr. Xu explains.

You need more than a drop of kindness

Inconsistent leaders may think that occasional kindness can make up for their harsh outbursts, but the study shows that this approach can backfire, amplifying the negative effects rather than mitigating them.

The research also highlights a surprising dynamic: even when employees aren’t directly subjected to a leader’s erratic behavior, they can still feel its negative effects. The study examined scenarios where a supervisor’s manager — their boss’ boss — swung between ethical and abusive behaviors. In such cases, employees observed the instability in their leader’s higher-up relationship, which caused a trickle-down effect of stress and uncertainty.

“In today’s workplaces, employees are very attuned to their supervisors’ relationships with more senior leaders,” Dr. Xu says. “If that relationship becomes unpredictable, or is marked by repeated bouts of good and bad behavior, it can cause real problems for the whole team.”

This phenomenon is what Dr. Xu calls “vicarious leadership.” When employees see their immediate supervisor being mistreated or inconsistently managed by higher-level executives, it erodes their confidence in that supervisor’s leadership abilities.

Important findings for organizations

For organizations, the research offers some important new insights. Most notable is the fact that leaders who seek to atone for intermittent bad behavior with brief spurts of supportiveness often do real harm to their employees. Researchers say organizations tend to be much more lenient when abusive bosses “are trying” from time to time, but this is not the way to go.

“Organizations tend to intervene when bosses are consistently abusive, but are more tolerant of leaders whose abusive behavior only shows through from time to time,” Dr. Xu says. “With this study, however, we’ve shown that intermittent bad behavior can actually be more toxic for organizations.”

The way to go would be anger management. Organizations should pay attention to employees who voice concerns and intervene even when dealing with sporadic bursts of negativity or abuse.

“This kind of intermittent abusive leadership tends to be impulsive,” Dr. Xu says. “That means there’s scope to reduce or eliminate it by helping leaders to manage their tempers and improve their impulse control.”

There are also signs that Jekyll-and-Hyde leadership can be “contagious”, with volatility in one leader fostering volatility and toxicity in the entire team. If volatility becomes normalized, it can lead to a breakdown in team cohesion and collaboration.

Haoying (Howie) Xu et al, Jekyll and Hyde leadership: Examining the direct and vicarious experiences of abusive and ethical leadership through a justice variability lens., Journal of Applied Psychology (2024). DOI: 10.1037/apl0001251