Raúl Esparza promoted to series regular, as confirmed by first appearance in the intro. Esparza was semi-regular cast the preceding season, having guest starred as Rafael Barba in eleven episodes.
Pablo Schreiber is cast as William Lewis. He also previously guest starred in an earlier season of Law and Order: SVU titled "Haystack (2007)" as a different character.
Pop star Taylor Swift is such a fan of the show that she named her pet cat 'Olivia Benson' in tribute to the lead character.