Judges in England and Wales will be given stronger powers to block prison visits and keep offenders in their cells for weeks on end if they refuse to face their victims' families during sentencing.
The tougher sanctions, due to come into effect next year, build on an existing law that orders criminals to attend sentencing or face being fined or jailed for another two years for contempt of court.
The move is the latest bid to push killers to attend court, with the Ministry of Justice (MoJ) acknowledging that longer jail time alone is unlikely to deter them if they are already behind bars.
"Criminals should not be able to pick and choose when they face justice," Prisons Minister Catherine McKinnell said.
"Refusing to turn up to sentencing is an insult to victims and their families, and offenders must face the consequences", she added.
The new measures mean offenders could be confined to cells for up to three weeks, social visits could be banned for nearly a month and any prison privileges revoked for longer.
Judges will also being able to restrict social visits further to once every four weeks for almost three months for criminals who refuse to attend sentencing.
For criminals aged 18-20, judges will be able to impose similar restrictions but for shorter periods of time, the MoJ said.
However, visits from prisoners' children will be exempt from the new sanctions.
But Pia Sinha, the CEO of Prison Reform Trust, has called for evidence that sanctions will increase attendance and warned the measures will punish relatives of prisoners who "have committed no offence themselves".
The families of murdered primary school teacher Sabina Nessa, law graduate Zara Aleena and mother-of-three Jan Mustafa have previously advocated for changes to the laws.
All of their loved ones' killers did not attend their sentencing hearings.
Thomas Cashman, the gunman who murdered nine-year-old Olivia Pratt-Korbel, and triple crossbow and knife killer Kyle Clifford, also refused to face their punishment in court.
Victims' Commissioner for England and Wales, Claire Waxman OBE, said the announcement follows "tireless efforts of victims' families" not accepting offenders simply "opting out of facing justice".
She said it was "essential" the powers were used "consistently by courts and prisons, so families receive the justice and accountability they deserve".