In 2019, New York’s legislature passed a law that allowed judges to consider a defendant’s documented history of surviving domestic abuse when determining what sentence to impose. If the judges found that the history played a role in the crime, they were able to reduce the sentences.

Since the law was enacted, prosecutors across the state, though, have at times requested that defendants waive that right in order to receive a plea deal and to avoid a trial.

But in an opinion on Thursday, New York’s highest court said prosecutors could not make defendants give up that right. In the 4-to-3 decision, written by Judge Jenny Rivera, the majority found that forcing a defendant to waive the right deprived them of the benefits of the 2019 law.

The practice “threatens to essentially eviscerate the statute by excluding the overwhelming majority of defendants who have suffered domestic violence,” Judge Rivera wrote.

Thursday’s decision also highlighted how an overwhelming majority of cases in the legal system end in plea agreements, rather than being decided at a trial. As of 2019, 96 percent of felonies and 99 percent of misdemeanors ended in a plea, according to state data.

The decision is one of the rare times that the state’s highest court has acknowledged a defendant’s rights cannot be set aside as part of a plea agreement, said Paris C. DeYoung, an attorney with Legal Aid who argued before the judges on behalf of the petitioner in the case.

“It’s very hard in our system to get the court to protect certain rights from waiver,” she said. “We’re excited that this sort of opens the door for folks to continue to pursue things that they are entitled to without having to deal with just another waiver on their plates.”

The case at the heart of the appeal was that of Nicole Hudson, who was charged with second-degree attempted murder and two counts of first-degree assault for running over her sister’s girlfriend with a car while fleeing her abusive ex-boyfriend. She took a plea deal and waived her right to have the abuse she had dealt with considered in her sentencing.

In a statement on Thursday, Ms. Hudson said the decision “has given me my life back.” Waiving away her ability to have the hearing before she was sentenced was “an injustice not just for me, but also for my child and for my family,” she said.

Oren Yaniv, a spokesman for the Brooklyn district attorney’s office, which prosecuted Ms. Hudson’s case, said the office was concerned the decision “will make it harder to resolve appropriate cases early.”

“Crime victims and surviving relatives deserve finality, clarity and a process that does not unnecessarily prolong painful experiences,” he said.

The law the decision aims to protect, the Domestic Violence Survivor’s Justice Act, was passed in 2019, when progressive Democrats had taken control of New York’s Legislature.

It allowed some defendants to have their history of domestic violence to be considered during sentencing if they showed that they were largely influenced by their abuse at the time of the crime. The judge could sentence the defendants to receive less prison time than what the law called for or alternative incarceration programs. It also gave people already in prison the opportunity to apply for resentencing.

The law came as crime in New York hit historic lows, and the Legislature overhauled parts of the state’s bail law and compelled prosecutors to hand over reams of case material to defense lawyers in a timely manner. However, as crime inched up after the pandemic, and after a public shift in sentiment on crime, lawmakers began to make changes to the policies. Both laws have been amended.

Ms. Hudson’s case began in 2019. She was at an outdoor party by her home when her abusive ex-boyfriend arrived. After an altercation broke out, during which her former boyfriend was injured, Ms. Hudson fled to her car and tried to escape. As she began driving away, she ran over her sister’s girlfriend, striking her three times and dragging her body down the street under the car. The woman was left permanently paralyzed and Ms. Hudson was charged with second-degree attempted murder and two counts of first-degree assault.

While her case was pending, Ms. Hudson, 34, asked that her history be reviewed by the court to see if she would be eligible to be sentenced under the domestic violence law. Her lawyers requested that the court sentence her to six months of incarceration and five years of probation.

Ms. Hudson’s lawyers included supporting information in her application, including a psychological report that said Ms. Hudson had experienced “repeated psychological and physical abuse” at the hands of her former boyfriend, who is also the father of her child. The first instance of physical abuse occurred when she was 20 years old and five months pregnant, the report found. His physical and verbal abuse escalated after.

While her application was pending before the court, Ms. Hudson was offered a plea deal through the Brooklyn district attorney’s office, offering her five years in prison and five years of probation. Their agreement, according to the opinion, was on the condition that she waive her right to the hearing to determine if she could get a reduced sentence.

Her lawyers objected to the provision, and the judge overseeing the trial also “expressed concern as to whether a defendant may waive,” the opinion said. However, the judge ultimately concluded that Ms. Hudson could waive her right and the court accepted her plea in 2021.

After she was sentenced, Ms. Hudson appealed, but the state’s Appellate Division found that the right could be waived. But the four judges on the state’s highest court on Thursday said that they agreed with a decision in another case that found some rights were “too valuable, both to the [defendant] and to the community, to be sacrificed in plea bargaining.”

Ms. Hudson said she was now “excited to finally have the chance to tell my story. I know that I caused great harm, and I take full accountability for that.”

“I also know that my actions came from my years of abuse,” she said.

But, in a dissent on Thursday, Judge Anthony Cannataro argued that a remedy should come from legislators and not from the judiciary.

Ms. Hudson’s case is an example of the sentencing law working, Judge Cannataro said, because she was offered the very lowest end of the ordinary sentencing range, “despite the serious and lifelong injuries that defendant inflicted.” Now, as a result of the decision, and the likelihood that prosecutors will withdraw the agreement, Ms. Hudson “may find herself subject to a far longer sentence than she agreed to,” he said.

There may still be survivors who will choose to plead guilty instead of going through the process to see if their case could be determined using the sentencing law, said Kate Mogulescu, a professor at Brooklyn Law School and part of the Surviors Justice Project.

“But what is not allowed now is for prosecutors to foreclose that,” she said. “That is an important distinction.”