Jonathan Davidson advises clients on trade, immigration, homeland security, economic security, critical infrastructure, congressional investigations, and oversight defense. He brings a unique combination of operational, legislative, and political strategic expertise, and his career has been defined by solving the hardest problems under the most difficult conditions.

Prior to joining WilmerHale, Mr. Davidson served as the Assistant Secretary of the Department of Treasury for Legislative Affairs and Chief of Staff of the Department of Homeland Security (DHS). He was deployed by the White House to these positions when each Department was under maximum pressure—first to Treasury when it was the legislative engine of the administration’s domestic agenda, then to DHS, which faced the most operationally demanding and politically complex issues confronting any department across the administration.

At Treasury, Mr. Davidson was part of the leadership team that delivered a historic period of legislative accomplishments and executed the implementation of landmark laws. He helped negotiate, pass, and implement signature fiscal achievements. Mr. Davidson co-led Treasury’s efforts to negotiate the single largest climate and clean energy investment in American history and was part of the core implementation team upon enactment—a role that required standing up entirely new tax credit delivery mechanisms, including elective pay (direct pay) and transferability provisions that allowed state and local governments, nonprofits, tribal entities, and US territories to access clean energy credits for the first time. He also led negotiations on the Fiscal Responsibility Act of 2023—the debt limit deal that averted a catastrophic federal default.

Mr. Davidson also managed Treasury’s congressional engagement on Russia/Ukraine sanctions (coordinating with the Office of Foreign Assets Control and the Financial Crimes Enforcement Network), outbound investment controls, Committee on Foreign Investment in the United States matters, global supply chain diversification, and a massive Internal Revenue Service funding increase. He also led the department’s response to the politically charged oversight demand for Suspicious Activity Reports related to the Biden family. 

At DHS, Mr. Davidson was part of the Secretary’s core team that managed the daily operations of a 240,000-employee department with 22 component agencies—the third-largest department in the federal government. This was an operational leadership position requiring coordination of simultaneous crisis responses across Customs and Border Protection, the Transportation Security Administration, the Cybersecurity and Infrastructure Security Agency, the Federal Emergency Management Agency, the US Secret Service, the Coast Guard, Immigration and Customs Enforcement, and 15 additional component agencies—each with distinct operational mandates, congressional oversight relationships, and regulatory responsibilities.

Mr. Davidson played a key role in the aftermath of a July 2024 assassination attempt of President Trump. At the direction of the Secretary, Mr. Davidson managed DHS’s institutional response—coordinating cooperation with an Independent Review Panel composed of former senior government leaders, while managing the department’s engagement with four other concurrent external investigation tracks: the House Oversight Committee, the House Bipartisan Task Force (which conducted 46 transcribed interviews, reviewed 20,000+ pages of documents, and issued 37 formal recommendations), the Senate Homeland Security and Governmental Affairs Committee (17 interviews, 75,000+ pages of documents), and a US Government Accountability Office investigation. In total, Mr. Davidson worked with counsel to coordinate the production of more than 95,000 pages of documents and the facilitation of more than 63 transcribed interviews across all five tracks—ensuring consistency across every production. He concurrently worked with the Secretary to drive the post-crisis operational reform process, working with agency leadership to address actionable findings and make other institutional improvements.  

Mr. Davidson also coordinated some of the federal government’s most consequential national security missions, including its mission to ensure the 2024 elections were secure against foreign interference and other threats. He played a central role in managing the DHS’s election security efforts through the Cybersecurity and Infrastructure Security Agency (CISA), which serves as the lead federal agency for election infrastructure protection. The 2024 election faced what CISA described as the most challenging threat environment to date—with Russia, China, Iran, and North Korea all conducting active operations to influence the outcome. Mr. Davidson oversaw DHS’s coordination of the defensive response across CISA, the Federal Bureau of Investigation, the Office of the Director of National Intelligence, US Cyber Command, and other federal partners during which CISA deployed Election Security Advisors to all 10 federal regions, conducted cybersecurity assessments with state and local election officials nationwide, and operated real-time threat monitoring throughout the election period.

Before his time in the executive branch, Mr. Davidson spent nearly three decades in senior positions on Capitol Hill. He served as Chief of Staff to Senator Michael Bennet (CO), Chief of Staff to former Senator Paul Sarbanes (MD), Chief Counsel to Senator Mark Warner (VA), and as Chief of Staff to former Representative John Sarbanes (MD). Mr. Davidson understands how oversight subpoenas are drafted, how hearing questions are structured, and how hearings are managed—not from briefing books, but from having done each of these things personally, over decades and from both sides of the dais. 

Additionally, Mr. Davidson ran one of the most successful defensive Senate campaigns in recent memory. As Chief of Staff to Senator Bennet, Mr. Davidson led the political operation that transformed the most vulnerable Democratic incumbent on the national map into a comfortable winner in the 2016 election cycle.