DISSENTERS are having a hard time at the moment. We see it in the intolerance of the Brexit debate, the no platforming by universities of controversial voices, or the shrill tribalism of social media. To differ is to risk derision.

It is ironic that lawyers are so skilled at taking sides yet prize few things more than collegiality. Ask law firm leaders to describe their organisations and ‘collegiate’ is always one of the first words out of the blocks. We’re a committed team here, striding as one towards a common goal, harmonious as Hamilton and focused as Attila the Hun. Well, as Kenny Dalglish might put it, mebbes aye, mebbbes naw.

Prized it may be, but there is good evidence that harmony in business is overrated and that, on the contrary, dissent is more valuable. In 2002, Professor Jeffrey Sonnenfeld of Yale School of Management set out to investigate what makes an effective company board. He looked at all the usual suspects: experience, gender balance, how big a stake the directors had in the business, the mix of younger members and grey heads, even regularity of attendance. He found many of them to be not that important. Two of America’s most notorious meltdowns, he noted - Enron and WorldCom - were stuffed with glitterati from the corporate elite. We all know of examples closer to home. This was his conclusion: “The highest-performing companies have extremely contentious boards that regard dissent as an obligation, and no subject as undiscussable.”

So is the key to getting on not getting on? It isn’t quite so simple. Dissent shakes up our assumptions. It compels us to ask how we can do better. Firms that encourage internal challenge are more likely to deliver great service, innovate, and attract the best people.

But context is all. Professor Sonnenfeld uses another important word: trust. Dissent has value only if it is driven by a sincere desire to achieve what is best for the whole business. As Brexit shows us so vividly, if it is motivated by a personal or sectional agenda, at best it will be a tiresome distraction, at worst utterly destructive.

Just as a business needs the right kind of dissent, so it needs the right kind of collegiality. True esprit de corps is a wonderful thing. I know this is deeply painful, but look how Gareth Southgate has transformed the mindset and performance of the England football team. However, not for nothing has collegiality been compared to the yeti: you hear quite a lot about it, but you don’t tend to see it very often.

It pays law firm leaders to ask themselves whether sometimes collegiality is a euphemism for tolerance of mediocrity; a reluctance to confront poor performance, or behaviour; a settling for same-old, same-old. Do colleagues truly put the firm before self-interest and clients before both? Do they think of clients as belonging to them or to the firm? Do their working practices, often ingrained over many years, need to change? Does the way they interact with clients and colleagues regularly drive people nuts? If the honest answers to questions like these cause concern they should, and quiet seething is not enough.

Collegiality happens when the firm signs up to a thoughtful, aspirational set of values, and then - this is the hard part - makes an implacable commitment to walk the walk. One of these values ought to be that expressing principled disagreement is not just a right, but an obligation, and that while once a decision has been made it has to be supported, passionate argument in reaching it is welcome.

A client of mine once startled his board by announcing: “From now on, sacred cows need to be scared cows.” He was honest enough to admit that this memorable epiphany began life as a typo, but then penicillin was also discovered by accident. “Whatever you do in life, surround yourself with smart people who will argue with you”, said John Wooden, the greatest-ever US basketball coach. It’s hard to disagree.

Stephen Gold is a solicitor and consultant to national and international law firms.