Gal Luft, promoted by House Republicans as possessing evidence of corruption by the Biden family, was charged by federal prosecutors with lobbying and sanctions violations and with brokering arms deals with China and Iran.
The shift by Mr. Lowell, one of Washington’s best-known scandal lawyers, highlights the blurry lines between self-promotion, access to power and the right to legal representation.
The acquittal of Thomas J. Barrack Jr., a former Trump adviser, showed the difficulty of proving wrongdoing amid a brew of political, personal and commercial interests.