Up to 350 more people could be refused bail each year as a result of law changes designed to prevent the release of serious offenders considered likely to offend again.
The changes are targeted at offenders such as those who killed teenagers Christie Marceau and Augustine Borrell. Christie was killed by Akshay Chand in 2011, and Augustine by Haiden Davis in 2007. Both Chand and Davis were on bail at the time.
The passing of the Bail Amendment Bill yesterday marked a fundamental shift in legal principles in New Zealand as it reversed the onus of proof for alleged offenders in bail cases. A person on a murder charge or repeat violence, drugs or sex charges would now have to prove why they should be bailed.
Under the previous law, the Crown had to show why defendants should be locked up.
It coincided with a campaign led by victims' families called "Christie's Law", which demanded even stricter bail laws including regular reviews of judges' decisions.
The movement was formed after Christie Marceau's death.
The law changes would not have prevented Christie's death - her killer was facing charges for kidnapping and assaulting her two months earlier but had a clear criminal record.
Justice Minister Judith Collins emphasised that future bail decisions would depend on how courts interpreted the legislation.
Judges would still have discretion in bail cases, but the change would cause them to look more carefully at higher-risk offenders.
Labour supported the bill. MP Phil Goff argued that individual cases such as Christie's were backed up by crime statistics.
One in five people reoffended while on bail. Most of these offences were minor, but there were some serious cases - between 2006 and 2010, 23 people were murdered by people on bail.
The Green Party opposed it because it felt it eroded the presumption of innocence until proven otherwise - a view shared by the Law Society and Human Rights Commission.
Mrs Collins said it was estimated that each year, 350 people who might have received bail before the law change might now be refused release.
New Zealand First MP Richard Prosser had tabled amendments which would have brought the bill into line with some of the demands of the Christie's Law group. He wanted the reverse onus of proof to apply to all people found guilty of serious offences and that it should be harder for 17 year-old offenders to get bail.
Mrs Collins said these issues, and closer monitoring of judges, were being looked at by a select committee.