U.S. Sen. Bob Casey; U.S. Reps. Allyson Schwartz, Bob Brady and Chaka Fattah, all of Philadelphia; Mayor Nutter; District Attorney Seth Williams; Police Commissioner Charles Ramsey; and officials from other Mid-Atlantic cities participated in the discussion, held at Girard College.
Wilmington Police Commissioner Christine Dunning said that she was on her way to the roundtable when she learned of the New Castle County Courthouse shooting, which left three people dead and two officers wounded.
Authorities said that the shooter, who was among the dead, killed the mother of his child and another woman at the entrance to the courthouse, where she was going to attend a hearing on a custody dispute between the estranged couple.
Those events, Dunning said, made her appearance in Philadelphia more significant.
"You basically should look at the national trends: It's just not only the courthouse - it's public places, it's movie theaters. And that's why it was so important for me to be here today," she said. "I know I have competent staff handling the thing in Wilmington along with the other police agencies, but we have to really put the sense of urgency that's needed with gun violence."
Obama will deliver his State of the Union address Tuesday night and is expected to continue his administration's push for federal gun regulations.
Biden said Monday that he would hold similar roundtable events across the country in the coming weeks to keep up the momentum of support for those measures.
Ramsey, president of the Major Cities Chiefs national police association, said that his group supported Obama's plan and thanked the vice president for including law-enforcement officials in the discussion.
"Obviously, Newtown, Conn., was a point that really got the attention of everyone in this country," he said. "We have our version of the Sandy Hooks and Columbines and Aurora, Colorados, almost every day on the streets."
Despite the event's serious tone, Biden did manage to squeeze in one characteristic quip, when asked for his thoughts on Pope Benedict XVI's decision to resign.
"I am not running," he said.
On Twitter: @SeanWalshDN