"This is not a victory. Zero murders would be a victory. But this is certainly progress," Chicago Police Supt. Garry McCarthy said.
Sixteen people were murdered in Chicago during March 2013, compared to 52 murders in the same month last year, Supt. McCarthy said. That's a decrease of 69-percent.
The homicide rate for the first three months of 2013 is down 42-percent, compared to the first quarter last year.
"It's noting these numbers, evaluating what works and re-enforcing what works and changing what doesn't work so we get better results," Chicago Mayor Rahm Emanuel said.
The mayor and superintendent credit a variety of factors, including police strategies that target violence-prone neighborhoods, after school programs, and much colder weather than during the same period last year.
At their news conference, the mayor and McCarthy repeated their calls for three-year, minimum prison terms for illegal gun possession despite the fact the Cook County Jail and state prisons are overcrowded.
"It's not just about putting people away. It's about putting the type of criminal that need to be away and off the street. Those that are committing gun crimes," Mayor Emanuel said.
As the city announced the murder rates, Cook County Board President Toni Preckwinkle said a $25 tax on firearm sales would begin despite the lawsuit filed against it.
"We try to do what's right and what we think is reasonable and then we defend ourselves in court," Cook County Board President Toni Preckwinkle said. She said tax revenue would help defray the cost of treating gunshot victims at county hospital.
Gun rights advocate Charles Butler called the county tax a "shell game" that will have no impact on gun violence.
"They're raising taxes on law-abiding citizens to pay for criminal activity?" Charles Butler, radio talk show host, said. "We keep electing people into office who think the only remedy to our problems is to raise taxes on law-abiding citizens."