Updated at 10:20 a.m. ETThe new head of the Consumer Financial Protection Bureau started work Monday — whoever that is.President Trump's pick to lead the consumer watchdog, Mick Mulvaney, arrived at the office early Monday morning with a bag of Dunkin' Donuts in hand. Mulvaney, the director of the Office of Management and Budget, is the acting director of the group until Trump can get a permanent leader through the Senate Confirmation process — at least, according to the Trump administration.But the former head of the CFPB, Richard Cordray, appointed Leandra English to lead the group in his absence. He named her as deputy director on Friday, his last day at the head of the group, hours before Trump named Mulvaney. English has since filed a complaint in U.S. District Court in Washington, D.C., to block the Trump administration's rival appointment.On Monday morning, English was communicating with CFPB staff through an all-staff email — which she signed as "acting director" — according to a source who spoke to NPR's Emily Sullivan. Meanwhile, Mulvaney was advising staff to disregard any instructions from English, according to Reuters. The dispute has left CFPB staff "scratching their heads over who was in charge," as Reuters reports.The dual appointments stem from partisan politics over the role of the bureau and from a dispute over which law governs filling an interim vacancy at the top. The 2010 Dodd-Frank Act, the law that created the CFPB, says it is the outgoing director's prerogative, but the administration says the Federal Vacancies Reform Act of 1998 reserves that appointment for the president.The complaint filed late Sunday by English says "the president's purported or intended appointment of defendant Mulvaney as Acting Director of the CFPB is unlawful.""The president may not, consistent with the statutory requirement of independence, install a still-serving White House staffer as the acting head of an independent agency," the suit reads.However, Politico reports that the CFPB's general counsel, Mary McLeod, has sided with the president. In a Nov. 25 memorandum obtained by Politico, McLeod writes: "As General Counsel for the Bureau, it is my legal opinion that the President possesses the authority to designate an Acting Director for the Bureau," adding, "I advise all Bureau personnel to act consistently with the understanding that Director Mulvaney is the Acting Director of the CFPB."Cordray was confirmed as head of the bureau in 2013, two years after being nominated by President Obama. But since Trump took office, he has found himself at frequent loggerheads with the administration, which has been openly disdainful of the bureau and its aims. Mulvaney has been among the harshest critics of the CFPB, the organization he's now tasked with leading.As NPR's Miles Parks wrote on Friday, "Because of the agency's broad mandate, whoever is empowered as director has a huge role in deciding what or how much the organization decides to regulate."Politico adds: