As more doctors help patients die, a debate rages over what constitutes 'unbearable suffering.' Here's everything you need to know:

What is 'assisted' dying?

Thousands of suffering people, most of them in Europe, are given lethal drugs each year to end their lives under a doctor's care. When the debate over the issue gained prominence in the 1990s, the medical community drew a distinction between euthanasia, when a doctor administers an injected dose to a person too ill to swallow drugs, and assisted suicide, in which the patient performs the deed. Since then, "assisted dying" has emerged as an umbrella term. The Netherlands was the first country to legalize the process, in 2002, followed closely by Belgium; the Dutch now see upwards of 6,000 assisted deaths annually, and Belgium had more than 2,600 last year. When it was first made legal, doctor-assisted death was seen as a way to spare terminally ill, pain-racked patients unnecessary suffering in their final days. But definitions of what kind of anguish is unbearable have in many cases widened over time, leading to debate about when a doctor is justified in helping a patient die.

Where is it legal?

The Netherlands, Belgium, Luxembourg, Canada, Switzerland, and Colombia. And last month, German courts overturned a 2015 law prohibiting assisted suicide, and the Portuguese parliament passed a bill to legalize it, although that bill has yet to be signed into law. In Australia and the U.S., the practice is legal in certain states. Patients sometimes cross borders in pursuit of aid in dying; since 2017, when Anne Bert, a French novelist suffering from the degenerative neurological disorder Charcot disease, publicized her intention to end her life in Belgium at age 59, Belgian clinics have seen a sharp increase in requests from French patients. We now get "one or two calls per week, compared with one every six months before," said Dr. François Damas. Most patients who desire the service, though, are too ill to travel for the necessary consultation, second opinion, and mandatory waiting period.

How are the criteria expanding?

Both Belgium and the Netherlands began allowing assisted suicide in 2002 for patients in "constant and unbearable physical or psychological pain" attested to by at least two doctors. The first to die that way were terminal cancer patients. But over the years, the criteria for "psychological pain" has been applied more and more broadly, and to more people without terminal illness. The Belgian law was expanded in 2014 to include minors, who must get their parents' permission to end their lives. In 2015, of the 2,022 patients who opted for euthanasia in Belgium, 299 did not have fatal illness. One case that drew debate and criticism in Belgium was that of deaf twins Marc and Eddy Verbessem, 45, who chose to die in 2012 because they were going blind and would soon be unable to communicate with each other. Of the 6,585 assisted deaths in the Netherlands in 2017, 83 cases cited psychiatric suffering alone.

Are there accusations of overuse?

Some activists say that helping depressed people kill themselves is not compassionate care. "Almost all serious psychiatric patients think that their situation is 'unbearable' and 'without perspective,'" says René Stockman, a priest and mental health expert with the Catholic order Brothers of Charity, citing the legal criteria patients must meet. There have also been highly publicized concerns over possible revocation of consent. In 2016, a Dutch dementia patient, 74, who had said in an advance directive written several years earlier that she would rather die than go into a nursing home, was sedated before being injected with a deadly drug cocktail. The woman, who was no longer lucid enough to understand what was happening, was restrained by her family when she woke up and began struggling during the procedure. Her physician, who was not named in court, became the first in the Netherlands to be tried for improper euthanasia; the doctor was acquitted last year.

How do supporters respond?

Supporters of assisted dying say that the safeguards are adequate, or even too onerous. They argue that thousands of nursing home patients — reliable statistics are impossible to come by — starve themselves to death each year. Canadian doctor Ellen Wiebe had a 102-year-old patient so desperate to end her agonizing spinal pain that she tried to kill herself in her nursing home using a pair of scissors. "This woman was clearly not depressed," Wiebe said. "I was so grateful that I could honor her wishes and end her suffering on her terms." Dignitas, the Swiss nonprofit founded in 1998 that has helped more than 3,000 people die surrounded by loved ones, says that its services are far preferable to letting ill people "make a lonely, risky suicide attempt."

What is the trend in the U.S.?

Oregon was the first state to legalize assisted dying, in 1997; since then California, Colorado, Hawaii, New Jersey, Washington, Vermont, and the District of Columbia have followed. Activists point to Oregon as evidence that legalization need not lead to a slippery slope of expanded criteria. Oregon's standards have not changed: Candidates must have a terminal illness that will cause death within six months, be over 18 and mentally competent, and be able to take the life-ending medication themselves. The practice remains relatively rare; in 2018, 168 people in Oregon died by assisted suicide.

The case of Tine Nys

Belgium's first criminal case concerning euthanasia was resolved Jan. 31, when three doctors were acquitted of unlawfully poisoning Tine Nys, 38, a heroin addict who had suffered from depression for years and had attempted suicide several times. Her parents and sister, present at her death in 2010, said she had not received adequate mental health treatment before her decision. Her sister, Sophie, said Nys may have manipulated the system by faking the tests to obtain an autism diagnosis. Because autism is "incurable and chronic," it meets one of Belgium's legal requirements for euthanasia. Nys' own psychiatrist refused her permission for assisted suicide; the doctor who approved it, Lieve Thienpont, diagnosed her with Asperger's syndrome and gave the go-ahead after meeting her just three times. But doctors said all procedures had been followed correctly, and the jury deliberated just eight hours before acquitting. Witnesses, including Nys' friends, said she had been "determined to die."

This article was first published in the latest issue of The Week magazine. If you want to read more like it, try the magazine for a month here.