Wilmer, Cutler, Pickering, Hale and Dorr was caught Wednesday in an email mix-up that revealed secret U.S. Securities and Exchange Commission and internal investigations at PepsiCo, after a Wilmer lawyer accidentally sent a Wall Street Journal reporter privileged documents detailing a history of whistleblower claims at the company.

The internal investigation revolves around PepsiCo’s 2011 acquisition of the Russian drinks company Wimm-Bill-Dann and the departure of general counsel Maura Smith in 2012 following allegations of financial misreporting and other wrongdoing at PepsiCo. A subsequent SEC investigation into Smith’s dismissal, and whether the company fired her in violation of whistleblower laws, is “at an early stage,” the Journal reported.

WilmerHale offices at 1875 Pennsylvania Avenue, NW, Washington, D.C. Oct. 3, 2012.