Richard was hired in 2008 by Carroll as a graduate assistant coach for the USC secondary (defensive backs). He followed Carroll to the NFL and joined his former team, the Seahawks, as secondary coach.
In an age of greater emphasis on player safety, Richard has built his secondary into a unit that plays aggressively, but still plays within the rules. For instance, Richard teaches his unit to limit their strike zone to the chest area in order to lessen the chance for penalties for illegal hits. His secondary's hard-hitting style has led it to be nicknamed "the Legion of Boom." In 2013, his unit was the stingiest secondary in the NFL, allowing the fewest passing yards in the league and helping lead the Seahawks to the first Super Bowl victory in franchise history. Bleacher Report described the Legion of Boom's accomplishments as a monument not only to Richard, but to Carroll, who was a safety himself in his playing days and began his coaching career as a secondary coach.