Nikhil Kumar: Over-regulated over there - New York fears for its mojo

In early 2007, on the eve of the global financial crisis, New York Mayor Michael Bloomberg and US Senator Chuck Schumer came together to warn that the city was at risk of losing its status as a world financial centre before the next decade was out.

They had commissioned the consultant McKinsey to prepare a report on the matter – and the conclusions were anything but positive. The ever-present threat of litigation, the burden of what was labelled "complex and unresponsive" regulation, and hurdles to hiring foreign staff were, the report claimed, blunting New York's edge.

Five years on and, to many observers, things look little different, with moans about how New York is losing – or has lost – its mojo rising like smoke-signals from the financial district in lower Manhattan. Earlier this year, for instance, a New York Times headline proclaimed: "London is eating New York's lunch." A cartoon map that ran alongside the piece showed the new financial towers of London standing high above the "Bay of Better Banking". Across the Atlantic, the Big Apple was shown besieged by "litigious hordes" and "thickets of tough rules".

Exhibit A, in the minds of those who lament New York's recent decline, is the Sarbanes-Oxley Act of 2002, conceived in the aftermath of the Enron and Worldcom scandals. Designed to head off future misdeeds, it imposed new reporting requirements on public companies. But Wall Street insisted that this only drove companies out of New York; they sailed off to London, where listing requirements were seen as less troublesome.

These concerns were, in fact, a key driver behind the 2007 Bloomberg/Schumer report. And today, they remains a bugbear for many who complain about New York's fading star, brandishing figures such as those showing that the average run rate for new listings has dimmed from more than 300 a year from 1980 to 2000 to around 100 a year between 2001 and 2009.

Not everyone agrees with what Jay Ritter of the University of Florida, Gao Xiaohui of the University of Hong Kong and Zhu Zhongyan of the Chinese University of Hong Kong have called the "regulatory overreach" hypothesis. They point instead to the trend of smaller companies being sold in trade deals instead going public.

Meanwhile, post-crisis regulation has also raised alarm in financial circles, most notably the Volcker Rule, part of the Dodd-Frank Act financial reforms of 2010.

Named for the former Federal Reserve chairman Paul Volcker, it limits the big banks' ability to gamble with their own money. Given its obvious – and indeed, intended – impact on the pre-crisis money-spinner of propriety trading, analysts expect it to weigh on Wall Street's big beasts, further denting the city's standing as the venue of choice for financial wheeler-dealers.

Overlaying all of this is the threat from what is a famously aggressive prosecutorial system. Just this week, federal lawyers accused Bank of America of saddling taxpayers with more than $1bn (£620m) worth of losses by selling toxic mortgages to the government-owned Fannie Mae and Freddie Mac, in a case that stems from its purchase of Countrywide Financial during the crisis.

Elsewhere, JP Morgan is facing a multibillion-dollar lawsuit connected to its purchase of Bear Sterns, which is being accused of misconduct in the packaging and sale of mortgage securities. And then there is the threat of private cases.

The epicentre of the Libor fixing scandal may have been London, but the first sign of legal aftershocks appeared in the US, when earlier this month news emerged of a possible class action against a number of big banks.