A prominent lawyer in Washington who defended Hunter Biden against criminal charges has launched a new law firm to represent former government officials and others targeted by the Trump administration.

Abbe Lowell left his large law firm, Winston & Strawn, to launch Lowell & Associates, which will defend clients including individuals, institutions and others that are “facing politicized investigations, civil and administrative actions”, the firm said in a Friday statement.

The new firm also includes two former lawyers at Skadden, Arps, Slate, Meagher & Flom who quit over its response to Donald Trump’s executive orders targeting the legal profession.

Skadden is one of nine firms that cut deals with the administration to avoid the Republican president’s crackdown on the legal industry. Four other firms have sued to block Trump’s orders, which restricted their business over the president’s claims that they had “weaponized” the legal system against him or his allies.

One of the ex-Skadden lawyers, Rachel Cohen, said there is a need for attorneys “willing to stand up to the government when it oversteps”.

Two other lawyers are also joining the new firm from Winston & Strawn.

Lowell is representing the New York attorney general, Letitia James, after the Trump administration referred her to the justice department for allegedly falsifying real estate records. James has denied the allegations.

The new firm said it was also representing clients fighting the cancellation of grant funding by the so-called “department of government efficiency” and the federal government.

Lowell represented Hunter Biden, former president Joe Biden’s son, against criminal gun and tax changes before he was pardoned in December. His clients have also included the former US senator Bob Menendez, Ivanka Trump and Jared Kushner.

The establishment of the new firm comes amid a broader effort to mount and sustain legal challenges to the Trump administration.

There are more than 200 lawsuits opposing key Trump policy initiatives, including efforts to curtail transgender and immigrant rights, and eliminating agency and grant funding.

The advocacy group Democracy Forward, which has filed more than 50 legal actions since the election, said this week it had hired Brian Netter, a former partner at Mayer Brown and a top attorney in the Biden-era justice department.

Netter said in a statement that he was joining the organization during “what may be the most consequential moment in the history of the US courts”.