Fair trading on Wall Street got a boost from the settlement announced two weeks ago between U.S. regulators and two investment banks over violations in operating alternative trading systems, known as “dark pools.” However, the fines totaling more than 4 million the two banks agreed to pay represent the cost of poor enforcement of existing laws and the failure to create precedents to act as deterrents, said experts at Wharton and the University of Missouri-Kansas City. Regulators need to increase their scrutiny of high-frequency trading, such as through dark pools, and identify systemic risks, if any, they added. The debate on regulatory approaches over alternative trading systems ensued after the Securities and Exchange Commission (SEC) announced that Barclays Capital and Credit Suisse Securities have agreed to settle cases involving violations of federal securities laws governing dark pools. The New York Attorney General’s office announced parallel actions against the two firms.…