In a 44-36 vote, the Democrat-run state assembly replaced the death sentence with life in prison without parole.
The bill is expected to be signed into law by Democratic Governor Jon Corzine - an opponent of the death penalty.
The move would make New Jersey the first US state to abolish capital punishment since the US Supreme Court reinstated executions in 1976.
Campaigners say they hope the vote in the New Jersey Assembly will encourage opponents of the death penalty elsewhere in the US.
Thirty-six of the 49 other states have the death penalty.
But fewer people were executed in America last year than at any time in over a decade.
The US Supreme Court is currently considering a legal challenge against the use of lethal injections.
Published: 2007/12/13 23:01:13 GMT
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