Aitan Goelman, head of CFTC Enforcement, announced his departure, effective February 3, during a broad exodus of prosecutors and regulators in the Obama administration’s final days. The departures, all expected, included Leslie Caldwell, the head of the Justice Department’s criminal division, Bill Baer, a senior Justice Department official, and Andrew Ceresney, who led the SEC enforcement division. Preet Bharara, the U.S. attorney in Manhattan, will be one of the few Obama appointees to remain in his post under the next administration.

In 2015, Mr. Goelman imposed the agency’s largest-ever penalty: an $800 million settlement with Deutsche Bank for manipulation of the London interbank offered rate (Libor). Late last year, Mr. Goelman took aim at Goldman Sachs for trying to manipulate another global benchmark, for fixed interest rate swaps (Isdafix). And just this month, the agency struck a $5 million settlement with Jon Corzine, who ran MF Global when it collapsed in 2011.

Meanwhile, the CFTC is without a chairman – given that the current chairman, Timothy Massad, is stepping down when Mr. Trump becomes president on Friday. Christopher Giancarlo, a Republican commissioner, will most likely become its interim leader and is reportedly under consideration to be nominated to become chairman.

Mr. Goelman said he expected the new administration to continue pressing cases of Wall Street wrongdoing. Still, he warned that the commission might not be able to do so if Congress deprives it of funding, a longtime source of tension between the agency and lawmakers. “There’s a lot of misconduct out there, some of which we need more money to catch,” Mr. Goelman said.

The need for resources took on greater importance as Mr. Goelman pushed for more cases to go to trial. As part of a new settlement policy, he generally offered defense lawyers the most generous proposal first. This approach, he said, provided a more credible threat of going to trial, which the agency did indeed do last year when it tried three cases, compared with only two trials in the last five or so years combined.