Mayer Brown, a leading global law firm, achieved an important victory on behalf of pro bono client Russell Caso Jr. in the US Court of Appeals for the DC Circuit on July 19, 2013. The court ruled that Mr. Caso, who served as chief of staff to a former US congressman, is entitled to have his honest-services fraud conviction overturned on the basis of actual innocence.

The court agreed with Mayer Brown’s argument that Mr. Caso’s conviction and sentence must be overturned because he is innocent of the charged offense, and he need not disprove other, less serious charges that the government claims it could have brought but never did. The court also agreed with Mayer Brown’s position that the seriousness of uncharged offenses must be measured by reference to the federal sentencing guidelines, rather than the statutory maximums considered by the district court.

Mayer Brown associate Scott Noveck (Washington DC), a member of the firm’s Supreme Court and Appellate practice, briefed the case. Former Mayer Brown partner Elizabeth Oyer, now an assistant federal public defender, argued the case before the DC Circuit.