Elizabeth Warren and Edward Markey, Massachusetts Democratic senators, sent a letter to the chairman of the Federal Energy Regulatory Commission (FERC) asking how the settlement with a JPMorgan Chase & Co unit was reached. The two senators asked Jon Wellinghoff if the recently-announced settlement with JPMorgan Ventures Energy Corp for allegations of power market manipulation in the California and Midwest markets included "adequate refunds to defrauded ratepayers."

The regulators earlier said the JPMorgan unit engaged in 12 manipulative bidding strategies between September 2010 and November 2012. JPMorgan Ventures Energy Corp earlier agreed on a USD 410 settlement with FERC. Under the terms of the settlement, JPMorgan will disgorge USD 125 million in profits while the remaining USD 285 million will serve as its civil penalty.

The two senators also inquired why the JPMorgan executives that FERC had accused "of stiff-arming its investigators by refusing to comply with subpoenas" would not be punished. Moreover, Warren and Markey also sought an explanation as to why the JPMorgan unit was allowed to get away without admitting their guilt.