New York, NY —

Newark is celebrating a milestone.

March was the first murder-free calendar month in more than 40 years. Mayor Cory Booker says great work by Newark's police is one big part of crime reduction.

"The other," he says, "has got to be more programs for people coming home from prison, because we're the land of the free, but we lock more folks up, and when they come out we create every disincentive for them to reengage and every obstacle to them succeeding. We have a 65 percent recidivism rate, and in Newark we now have some programs that have driven that down to less than 5 percent."

Booker spoke on MSNBC's "The Rachel Maddow Show."

The last time Newark went through a calendar month without a murder was 1966, though two years ago, the city had 43 murder-free days spanning parts of January and February.

Police say ten people have been murdered in the city in the first quarter of 2010, the same number as last year, but the second-lowest since 1941. Other violent crimes are down an average of 14 percent compared to a year ago, and shooting incidents are down 18 percent.