Jenner & Block's pro bono work dates back to at least the 1950s, when a small group of the firm's lawyers began representing indigent criminals in Chicago's courtrooms.

Fast forward to 2016 and the growth of the firm's pro bono program can be viewed by the amount of work its lawyers do before the U.S. Supreme Court. Last year, the firm successfully argued six cases before the high court, winning results including solidifying the law banning execution of the intellectually disabled, defending a challenge to re-districting, and protecting the rights of adoptive parents in same-sex relationships.

The high court work, including a high number of oral arguments presented by associates, contributed to the firm's more than 75,000 hours of pro bono work last year. Across the firm, lawyers averaged 138 hours of pro bono work, and nearly 94 percent did more than 20 hours of donated time.