Mayer Brown has added senior government lawyer Kimberly Hamm in Washington DC to lead its congressional investigations group.  

Hamm has joined the firm’s litigation and dispute resolution and public policy, regulatory and government affairs practices as a partner following a stint as chief counsel to the former US Speaker of the House of Representatives Kevin McCarthy.  

Hamm is one of very few lawyers to have held senior positions at the top levels of the legislative branch and US Securities and Exchange Commission, having earlier also served as chief counsel to former SEC chairman Jay Clayton. 

“Kim is a highly respected congressional investigations lawyer with exceptional experience working at the highest levels of government,” said Richard Spehr, the global leader of Mayer Brown’s litigation and dispute resolution practice. “Our clients will greatly benefit from her counsel on navigating complex investigations as well as the financial regulatory and legislative landscape in the United States.” 

Mayer Brown’s investigations practice and focus on financial services dovetails nicely with Hamm’s experience, which includes a year-long stint in the public policy group at BlackRock, where she led advocacy and external engagement in the areas of financial stability, corporate governance and regulatory frameworks impacting mutual funds.  

From 2003 she spent more than a decade in the litigation department of Simpson Thacher & Bartlett and from there joined the House of Representatives’ Office of General Counsel in 2014, where she advised committees on congressional investigations and represented House members and committees in grand jury, trial and appellate proceedings. 

She joined the SEC in 2019 and as chief counsel to Clayton she oversaw regulatory initiatives across all divisions of the SEC, including the issuance of more than 45 final rules.  

Hamm joined McCarthy’s office in April last year as deputy general counsel and was promoted to general counsel the next month. As chief counsel to Speaker McCarthy, who was controversially ousted in October, she provided guidance to House committees on congressional investigations and oversight, including issuance and enforcement of committee subpoenas to agencies and private parties. 

Liz Stern, managing partner of Mayer Brown’s Washington DC office, said the firm was ‘thrilled’ to welcome Brown, adding that she would “strengthen our ability to represent clients – particularly financial services companies – in congressional investigations and other high-profile governmental actions.” 

At Mayer Brown Hamm will work alongside a growing roster of former senior government officials, including US Deputy Secretary of State and Ambassador John Sullivan, former White House National Economic Council Deputy Director Andrew Olmem, former chief of staff to Senator Amy Klobuchar, Jonathan Becker, and former Department of Justice official Adam Hickey. 

“Businesses today must contend with reputational and legal risks across many fronts, particularly concurrent investigations by Congress, state attorneys general and federal agencies,” Hamm said. “My experience will allow me to advise clients on these uniquely complex matters that require both legal expertise and political judgement.” 

Willkie Farr & Gallagher bolstered its ranks in Washington DC recently with a senior government lawyer, hiring Timothy Heaphy, the chief investigator to the US House committee investigating the 6 January 2021 attack on the US Capitol to co-lead its compliance, investigations and enforcement practice.   

Last summer O’Melveny & Myers also hired a former acting deputy director of the US Patent and Trademark Office, Coke Morgan Stewart, as senior counsel.