[13] Freis joined the United States Department of the Treasury in September 2005 as the first-ever Deputy Assistant General Counsel for Enforcement & Intelligence.

[16][17][18] Freis was appointed Director (CEO) of the Financial Crimes Enforcement Network (FinCEN) on March 5, 2007, by United States Secretary of the Treasury Hank Paulson.

"[19] FinCEN had faced criticism from the financial industry over difficulties of complying with anti-money laundering regulations,[20] which had been expanded in 2001 under USA PATRIOT Act, Title III.

[32] The final rule was issued in 2016,[33] at which time President Obama in referencing the regulation “call[ed] on Congress to pass new legislation that requires all companies formed inside the United States to report information about their real owners to the Treasury Department's Financial Crimes Enforcement Network.

[40] Under Freis, FinCEN worked closely with counterpart regulators and the financial intelligence unit in Mexico, and in law enforcement efforts along the Southwest Border.

[2] In January 2013, Freis joined the international law firm Cleary Gottlieb Steen & Hamilton as counsel based in its Washington, D.C., office.

[49] Based in Frankfurt, Germany, the international financial market infrastructure provider includes the Frankfurt Stock Exchange; the Eurex Exchange offering futures and options derivatives; Eurex Clearing central counterparty (CCP); Clearstream, the International Central Securities Depository (ICSD); commodities and FX trading platforms; and various IT, financial index providers, and analytics businesses.

[50][51] On May 8, 2020, Wirecard AG, the payments processor and financial services provider based in Germany announced that effective July 1, 2020, James Freis would be joining as executive board member[52] ("Vorstand").

Wirecard had faced criticism and allegations of accounting irregularities over the prior two decades as it grew globally, but that notwithstanding, by 2018 it had become a member of the DAX stock index[53] of German blue chip companies.

Freis's appointment was described as part of a "comprehensive change" in the management board, and he would be responsible for a newly created department "Integrity, Legal and Compliance."

"[54] On June 18, 2020, Wirecard announced Freis had joined the management board with immediate effect, earlier than his planned start date of July 1.

[57][58] Working through the night to investigate, Freis quickly concluded that there was obvious fraud in the purported Wirecard accounts and in the morning informed the supervisory board.

Opposition lawmakers characterized the Wirecard scandal as a “collective failure of supervision”, criticizing numerous government authorities, the board of directors, and auditors.

[71] He is active with fintech and startup companies, including these affiliations: As an attorney, Freis is a member of the bar associations of New York, New Jersey and the District of Columbia.