The second San Francisco man charged with assaulting members of the Baker’s Dozen a cappella group has entered a plea of not guilty.

Richard Aicardi, 19, who is charged with two counts of assault and one count of battery against Evan Gogel ’10 and William Bailey ’10, appeared alongside Brian Dwyer, 19, who is charged with one count of assault and one of battery against Gogel, in San Francisco Superior Court on Monday. Dwyer pleaded not guilty to the charges yesterday, while Aicardi entered his not guilty plea in early March.

There have been no new developments relating to the possibility of charges being filed against Aicardi, Dwyer and other suspects in the attack on Sharyar Aziz ’10, the most seriously injured victim of the fight, the San Francisco District Attorney’s office said Monday. Aziz is currently preparing a civil lawsuit against his five alleged attackers.

In an incident that made national headlines, the all-male singing group was assaulted while leaving a New Year’s Eve party thrown in their honor during their winter singing tour. Several singers suffered injuries, including a broken jaw, a concussion, a sprained ankle and black eyes. Aicardi and Dwyer are the only suspects who have been charged with felony assaults, though witnesses have said that over a dozen men attacked the Yale students.

Attorneys for both defendants have maintained that the injuries sustained by a cappella group members were the result of a mutual combat situation fueled by the consumption of alcohol at the party.

Members of the Baker’s Dozen declined to comment Monday night.

Aicardi and Dwyer are due back in court on May 15.