Former Barclays Chief Executive Bob Diamond was questioned on Wednesday about inter-bank interest rate fixing. (Matthew Lloyd/GETTY IMAGES)

While most of us were attending barbeques or heading to Fourth of July picnics Wednesday, outgoing Barclays CEO Bob Diamond was getting grilled in a parliamentary hearing over his bank’s role in an interest rate manipulation scandal that is set to expand to other institutions. Amid questions about the bank’s actions, the now former CEO also mentioned Barclays’ “no jerks rule,” which makes it a practice to drop employees who might be productive but whose behavior is unethical, not collegial, or particularly boorish.

It wasn’t the first time Diamond talked about the policy. Press reports in 2011 said some 30 people had lost their jobs as a result of the rule at Barclays; Diamond has said it came about while he ran the firm’s investment banking division. And he’s hardly alone in its practice. While it’s difficult to know how many organizations started up a “no-jerks policy” following the publishing of Stanford University business professor Robert Sutton’s bestseller, The No A—hole Rule , the idea has taken off. Sutton is careful to say he didn’t invent the concept, but his wildly successful book struck a nerve with people fed up with their workplaces’ arrogant bullies. The book has been translated into languages ranging from Croatian to Polish to Japanese.

But one problem with popular management or leadership ideas is that too many places institute them thinking they’ll be a cure-all, rather than key tools for cultural change. Sutton himself is careful in his book, for example, to say that leaders who try to make a rule which weeds out bad apples can’t be all talk. “If you can’t enforce the rule,” he writes, “it is better to say nothing. Otherwise, your organization risks being seen as both nasty and hypocritical.”

He also reminds readers that “the rule lives—and dies—in the little moments.” In other words, “having all the right business philosophies and management practices to support the no a—hole rule is useless unless you treat the person right in front of you, right now, in the right way.” It’s also not just leadership’s job: “The no a—hole rule works best when everyone in the organization steps in to enforce it when necessary,” he writes. It must become part of the culture and everyday behavior, not just a snappy little rule discussed by the organization’s top leadership and H.R. department.

Who knows how seriously Diamond’s “no jerks” policy was taken at Barclays. Diamond may have known that cultural change has to be “embedded in an organization,” and the traders who wrote flippantly about rigging interest rates (“Dude. I owe you big time! Come over one day after work and I'm opening a bottle of Bollinger”) may have been an aberration rather than the rule. But it’s a reminder that just because a leader decides to adopt a certain management concept doesn’t mean it will root out all the people who are a problem.

I like the idea of a “no jerks” rule. It puts into simple terms how it’s too easy to overlook demeaning and toxic behavior when people turn out impressive performance. But, as I’d guess Sutton would agree, it can’t stand alone. Incentives have to change. Hiring practices have to be rethought. Pay structures have to be altered (Diamond’s £17 million payday last year probably didn’t do much to promote humility, for instance). And everyone has to embrace the idea through watching the behavior of the people around them. 

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