An association of police chiefs called the U.S. Senate's rejection of gun-control legislation earlier this month "a disgrace" and blamed "the gun lobby" for blocking the measures.

In a statement released Tuesday, the Major City Chiefs Association said several "weak Senators" failed to support expanded background checks and other "common-sense measures." The statement was signed by Charles Ramsay, the group's president and Philadelphia's police commissioner.

On April 17, Senators voted 54-46 on the Manchin-Toomey amendment. The amendment needed 60 votes to move ahead. The legislation would have extended background checks to purchases at gun shows and online retailers. Senators also rejected a new assault weapons ban and magazine capacity limit.

"We looked to the U.S. Senate for courage and leadership on gun violence, to enact reforms that are long overdue," Ramsay wrote. "With 94 % of the public asking for better gun laws, we expected the Senate to do what cops do—protect the public. But a minority of Senators protected themselves instead of the American people. That's a disgrace."

Ramsay said Senators disregarded the wishes of the victims' families from the Sandy Hook Elementary School shooting.

"Showing an unprecedented lack of courage, U.S. Senators defied the will of the American people and voted according to their instructions from the Washington gun lobby," Ramsay wrote. "Much was said about the rights of gun owners, but almost nothing was said about the equal rights of the public to be safe from gun violence."