A separation of the Big Four's audit functions into separate businesses would dramatically speed up their expansion into the legal services market, according to various market executives.

Following the surge of MPs calling for an industry overhaul of the Big Four in the wake of scandals such as BHS and Carillion, the Competition and Markets Authority (CMA) last month (April 2019) published recommendations for an audit separation. Ernst & Young, Deloitte, KPMG and PriceWaterhouseCoopers could now be forced to hive off their audit function into separate entities, to reduce their market dominance

Since then, the Big Four have published statements saying they welcome the discussions, but have no plans as yet to split their operations, with some firms criticising parts of the CMA's suggestions.

EY is now taking seeking to challenge the competition watchdog's bid, bringing in Slaughter and May for advice.

If splits do occur it would have a dramatic effect on the Big Four's legal arms, market participants believe.

Mark Vorsatz, chief executive of consultants Andersen Global, believes the change would result in a major push by the Big Four, which he describes as "sleeping giants".

He said that up until this point, the Big Four's legal arms have faced limitations due to conflicts of interest from their auditing bodies, but added: "If they truly separate it, they won't have the independence issues or restrictions on scope of practice… and if there's no independence issues, you would see an expansion of legal services, making them more and more just like other law firms."

Vorsatz said his conversations have revealed a new wave of fear among law firms as to how the legal arms may react in the case of audit separation.

Nick Jarret, from law firm consulting company Edge International, said: "The thing about accountancy firms is that they offer a limited range of services. If we look back to the 20th century, they began to take tax advice away from traditional law firms and they've been looking at doing more and more of this. If their audit function is given new restrictions, they'll be even more anxious to diversify their practices."

He said that revenue decline would mean the Big Four would look for other ways to get income: "And this could include all the typical methods, including being more aggressive in their legal function.

"The accountancy firms have the firepower to make a real dent in the market," Jarret said.

Since being granted legal practice licences, the Big Four accounting firms have grown their legal divisions to a combined total of more than 10,500 lawyers in more than 100 countries.

The possibility of expansion represents a real shift in tactics, which law firm competitors are closely eyeing. Eversheds Sutherland co-chief executive officer Lee Ranson said when the Big Four launched, they intended to advise in limited practice areas. He told Legal Week: "Those barriers have been eroded over time and this erosion will now continue even more. I expect they'll start to compete in the M&A [and] transactional spaces if their audits split."

It has not yet been confirmed whether the audit firms will be required to separate or what exactly the nature of the split might be. Currently, the debate is whether it would be a devolved audit arm with far less information-sharing between audit and the rest of the business, or a complete split that would mean the audit functions are an entirely different entity.

But one former Big Four partner doubts an audit split would spark too much of a battle in the legal market, because the accountants' brand would be weakened.

He said: "If the legal arm is freed from the audit practice, then they've got the freedom to compete alongside other law firms alike. But that would also mean they've lost their USP – their strength is that they're embedded within the overall brand. If you separated their legal arms right now and ranked them alongside other law firms, they'd be f*cked."

But Andersen's Vorsatz maintains that while the overall business could face a setback initially, the damage will only lead the legal arms to launch a fresh attack.

He said: "With the resources the Big Four have, if they put in place the financial support to expand then they could expand very rapidly and aggressively.

"If the handcuffs come off, they are not going to hold back."