Dechert's high-profile criminal, investigations and civil fraud unit is breaking away from the firm to launch an independent boutique

Highly-regarded litigation head David Byrne and partners Matthew Frankland and Bernard O'Sullivan have negotiated the exit with Dechert because they want to continue acting for legally aided, as well as privately funded, clients. Dechert has a legal aid franchise for criminal work on the back of the practice, making it highly unusual among City firms.

Frankland said: “We've always held our own in terms of budget and bringing in decent high-profile work, but the changes to legal aid are going to make it harder and harder to do that [in a large commercial firm].”

The team decided against reinventing itself with a focus on financial services, a key Dechert strength. “We were concerned that if we didn't move away from doing large criminal legally aided work, we were going to struggle in terms of revenue targets. A firm is a commercial enterprise and for that reason I raised my concerns with the chairman that the revenue schemes were not going to be what we would want them to be in a firm of this kind with the overheads it has,” said Frankland.

UK managing partner Steven Fogel said the practice did not fit with Dechert's strategy and profit model. “David Byrne and I have often asked the question strategically about the fit, but we've been happy to work together. But now the issue is one of David wanting to construct an environment where he can transition the practice at his own pace to meet the challenging new rules [affecting legal aid].”

He added: “There is certainly an economic issue as to whether we ought to have that type of practice in the size of firm we are.”

The team's recent high-profile work has included acting for the former dictator of Nigeria, General Sani Abacha, over the looting of billions of dollars of public money and for defendants in last year's collapsed bootleg alcohol prosecutions involving bonded warehouses.

The group is still in discussions with the firm as to how many other fee-earners will move with them.