Why Is It So Hard To Agree On When Human Life Starts?

12:13 minutes

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This story is a collaboration between Science Friday and KHN. It was written by Sarah Varney.

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Credit: Eric Harkleroad, KHN illustration; Getty Images; Unsplash.

As life-preserving medical technology advanced in the second half of the 21st century, doctors and families were faced with a thorny decision, one with weighty legal and moral implications: How should we define when life ends? Cardiopulmonary bypass machines could keep the blood pumping and ventilators could maintain breathing long after a patient’s natural ability to perform those vital functions had ceased.

After decades of deliberations involving physicians, bioethicists, attorneys, and theologians, a U.S. presidential commission in 1981 settled on a scientifically derived dividing line between life and death that has endured, more or less, ever since: A person was considered dead when the entire brain—including the brainstem, its most primitive portion—was no longer functioning, even if other vital functions could be maintained indefinitely through artificial life support.

In the decades since, the committee’s criteria have served as a foundation for laws in most states adopting brain death as a standard for legal death.

Now, with the overturning of Roe v. Wade and dozens of states rushing to impose abortion restrictions, American society is engaged in a chaotic race to define the other pole of human existence: When exactly does human life begin? At conception, the hint of a heartbeat, a first breath, the ability to survive outside the womb with the help of the latest technology?

That we’ve been able to devise and apply uniform clinical standards for when life ends, but not when it begins, is due largely to the legal and political maelstrom around abortion. And in the two months since the U.S. Supreme Court issued its opinion in Dobbs v. Jackson Women’s Health Organization, eliminating a long-standing federal right to abortion, state legislators are eagerly bounding into that void, looking to codify into law assorted definitions of life that carry profound repercussions for abortion rights, birth control, and assisted reproduction, as well as civil and criminal law.

“The court said that when life begins is up to whoever is running your state — whether they are wrong or not, or you agree with them or not,” said Mary Ziegler, a law professor at the University of California-Davis who has written several books on the history of abortion.

Unlike the debate over death, which delved into exquisite medical and scientific detail, the legislative scramble to determine when life’s building blocks reach a threshold that warrants government protection as human life has generally ignored the input of mainstream medical professionals.

Instead, red states across much of the South and portions of the Midwest are adopting language drafted by elected officials that is informed by conservative Christian doctrine, often with little scientific underpinning.

A handful of Republican-led states, including Arkansas, Kentucky, Missouri, and Oklahoma, have passed laws declaring that life begins at fertilization, a contention that opens the door to a host of pregnancy-related litigation. This includes wrongful death lawsuits brought on behalf of the estate of an embryo by disgruntled ex-partners against physicians and women who end a pregnancy or even miscarry. (One such lawsuit is underway in Arizona. Another reached the Alabama Supreme Court.)

In Kentucky, the law outlawing abortion uses morally explosive terms to define pregnancy as “the human female reproductive condition of having a living unborn human being within her body throughout the entire embryonic and fetal stages of the unborn child from fertilization to full gestation and childbirth.”

Several other states, including Georgia, have adopted measures equating life with the point at which an embryo’s nascent cardiac activity can be detected by an ultrasound, at around six weeks of gestation. Many such laws mischaracterize the flickering electrical impulses detectible at that stage as a heartbeat, including in Georgia, whose Department of Revenue recently announced that “any unborn child with a detectable human heartbeat” can be claimed as a dependent.

The Supreme Court’s 1973 decision in Roe v. Wade that established a constitutional right to abortion did not define a moment when life begins. The opinion, written by Justice Harry Blackmun, observed that the Constitution does not provide a definition of “person,” though it extends protections to those born or naturalized in the U.S. The court majority made note of the many disparate views among religions and scientists on when life begins, and concluded it was not up to the states to adopt one theory of life.

Instead, Roe created a framework intended to balance a pregnant woman’s right to make decisions about her body with a public interest in protecting potential human life. That decision and a key ruling that followed generally recognized a woman’s right to abortion up to the point medical professionals judge a fetus viable to survive outside the uterus, at about 24 weeks of gestation.

In decisively overturning Roe in June, the Supreme Court’s conservative majority drew on legal arguments that have shaped another contentious end-of-life issue. The legal standard employed in Dobbs — that there is no right to abortion in the federal Constitution and that states can decide on their own — is the same rationale used in 1997 when the Supreme Court said terminally ill people did not have a constitutional right to medically assisted death. That decision, Washington v. Glucksberg, is mentioned 15 times in the majority opinion for Dobbs and a concurrence by Justice Clarence Thomas.

Often, the same groups that have led the fight to outlaw abortion have also challenged medical aid-in-dying laws. Even after Dobbs, so-called right-to-die laws remain far less common than those codifying state abortion rights. Ten states allow physicians to prescribe lethal doses of medicine for terminally ill patients. Doctors are still prohibited from administering the drugs.

James Bopp, general counsel for the National Right to Life Committee who has been central to the efforts to outlaw abortion, said that both abortion and medically assisted death, which he refers to as physician-assisted suicide, endanger society.

“Every individual human life has inherent value and is sacred,” said Bopp. “The government has the duty to protect that life.”

Both issues raise profound societal questions: Can the government keep a patient on life support against his wishes, or force a woman to give birth? Can states bar their own residents from going to other states to end a pregnancy, or prohibit out-of-state patients from coming in to seek medically assisted death? And who gets to decide, particularly if the answer imposes a singular religious viewpoint?

Just as there are legal implications that flow from determining a person’s death, from organ donation to inheritance, the implied rights held by a legally recognized zygote are potentially vast. Will death certificates be issued for every lost pregnancy? Will miscarriages be investigated? When will Social Security numbers be issued? How will census counts be tallied and congressional districts drawn?

Medical professionals and bioethicists caution that both the beginning and end of life are complicated biological processes that are not defined by a single identifiable moment — and are ill suited to the political arena.

“Unfortunately, biological occurrences are not events, they are processes,” said David Magnus, director of the Stanford Center for Biomedical Ethics.

Moreover, asking doctors “What is life?” or “What is death?” may miss the point, said Magnus: “Medicine can answer the question ‘When does a biological organism cease to exist?’ But they can’t answer the question ‘When does a person begin or end?’ because those are metaphysical issues.”

Ben Sarbey, a doctoral candidate in Duke University’s department of philosophy who studies medical ethics, echoed that perspective, recounting the Paradox of the Heap, a thought experiment that involves placing grains of sand one on top of the next. The philosophical quandary is this: At what point do those grains of sand become something more — a heap?

“We’re going to have a rough time placing a dividing line that this counts as a person and this does not count as a person,” he said. “Many things count as life — a sperm counts as life, a person in a persistent vegetative state counts as life — but does that constitute a person that we should be protecting?”

Even as debate over the court’s abortion decision percolates, the 1981 federal statute that grew out of the presidential committee’s findings, the Uniform Determination of Death Act, is also under review. This year, the Uniform Law Commission, a nonpartisan group of legal experts that drafts laws intended for adoption in multiple states, has taken up the work to revisit the definition of death.

The group will consider sharpening the medical standards for brain death in light of advances in the understanding of brain function. And they will look to address lingering questions raised in recent years as families and religious groups have waged heated legal battles over terminating artificial life support for patients with no brain wave activity.

Bopp, with the National Right to Life Committee, is among those serving on advisory panels for the effort, along with an array of doctors, philosophers, and medical ethicists. The concept of “personhood” that infuses the anti-abortion movement’s broader push for fetal rights is expected to be an underlying topic, albeit in mirror image: When does a life form cease being a person?

Magnus, who is also serving on an advisory panel, has no doubt the commission will reach a consensus, a sober resolution rooted in science. What’s less clear, he said, is whether in today’s political environment that updated definition will hold the same sway, an enduring legal standard embraced across states.

KHN (Kaiser Health News) is a national newsroom that produces in-depth journalism about health issues. Together with Policy Analysis and Polling, KHN is one of the three major operating programs at KFF (Kaiser Family Foundation). KFF is an endowed nonprofit organization providing information on health issues to the nation.

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Segment Guests

Sarah Varney

Sarah Varney is a senior correspondent at Kaiser Health News in Monterey, Massachusetts.

Segment Transcript

IRA FLATOW: This is Science Friday. I’m Ira Flatow. Just over 40 years ago, medical professionals came up with a way to define what it means for a person to die, what defines human death. Advances in medicine have made it possible to keep people alive in ways that– well, they were never possible in the past. So hospitals and doctors around the country adopted a set of standards which constitute what’s called brain death. And those same standards were codified into laws in nearly every state.

But there’s no such medical consensus for another big question– when does human life begin? And with the overturn of Roe v. Wade, the answer to that question has big implications. As part of our continuing coverage of the science behind reproductive health, meet Sarah Varney, senior correspondent for Kaiser Health News, who also focuses on reproductive health. She’s based in Monterey, Massachusetts. Sarah, welcome to Science Friday.

SARAH VARNEY: Thanks, Ira.

IRA FLATOW: Nice to have you. OK, let’s start off. Can you take me through perhaps a brief history of how our definition of death has shifted as medicine has advanced?

SARAH VARNEY: So really until the 1950s, physicians in the United States and really around the world would do what you might think. They would feel for a pulse or listen for breathing. They might even hold a mirror up to a patient’s nose to look for condensation. Then, by the 1950s or so, scientists had developed these mechanical ventilators, and they could really keep people, even with catastrophic brain injuries, alive almost indefinitely. So there was this big question about whether patients would even want to stay alive under these conditions. And even in the most existential sense, this sort of raised this question of what it meant to be a human being.

And then in 1967, there was this South African surgeon who performed the first heart transplant. And that ushered in a whole new era of organ transplantation. And these questions about whether some of these patients were truly dead enough to donate their organs took on a greater urgency.

And then, in the late 1960s, there were a number of groups around the world that were starting to weigh these questions. That included, also, this ad hoc committee at Harvard Medical School. And it was a committee that was made up of doctors, a bioethicist, a lawyer, a theologian, and the central question that they were trying to answer was, if someone is seemingly irreversibly unconscious, are they dead?

So in 1968, this committee developed what became known as the criteria for determining what was essentially a new way to die. And it was called an irreversible coma, what you referred to as brain death. And these are patients who were unresponsive. They showed no movement or reflexes. And there was a test that registered their electrical activity in the brain, called an electroencephalogram. And that test would show that their electrical activity in their brain was essentially flat.

IRA FLATOW: So was this codified, then, as to what death was, this brain death?

SARAH VARNEY: So by 1981, there was this presidential commission established. What they wanted was a uniform definition of brain death across all the states. And they decided that the entire brain– so that included the brain stem– basically irreversibly ceased to work. So the person, at that point, could be declared brain dead.

IRA FLATOW: And so the committee reached this conclusion after it had studied it intensely with medical professionals and experts, right?

SARAH VARNEY: That’s right. I mean, they had neuroscientists. They had bioethicists. And they spent months and months and months and months debating this and essentially came to a medical definition of what it meant to be brain dead.

IRA FLATOW: And even with the uniform definition of brain death, there have been cases, high-profile legal fights over brain-dead patients, that challenge this notion of brain death. And it’s all been based on religious or moral and ethical grounds. Talk about the case– this one case is the story of a 13-year-old girl named Jahi McMath.

SARAH VARNEY: So she suffered an irreversible brain damage after a complex tonsil surgery. And she was declared deceased in California. Now, McMath’s family, with the financial support from pro-life groups at the time, moved the girl’s body to New Jersey. Now, New Jersey is a state that– it differs from these other states around the country in that it allows families to contest a declaration of brain death. So when McMath’s body was moved to New Jersey, she became legally alive again.


SARAH VARNEY: She had no detectable brain activity for nearly five years. And during that time– here’s what’s so fascinating, Ira– is she actually went through puberty and started menstruating. And she did eventually die in 2018.

IRA FLATOW: Wow. So how might this case help us better understand how hard it is to draw the line when someone has died?

SARAH VARNEY: So the case of McMath is really fascinating. And part of the reason she was able to go through menstruation is because of the hypothalamus. And the hypothalamus, while it sits in the brain, it really wasn’t something that was covered by this total brain death standard. So about half of all brain-dead adult patients, their hypothalamus can actually be stimulated, and you can get a response. And so now, actually, there is this committee that is meeting once again to refine this definition of brain death. And one of the things that they are considering is, how do we treat the hypothalamus when we’re declaring somebody brain dead?

IRA FLATOW: Right. Wouldn’t you agree that, despite some of the nuances we just talked about, that there is widespread medical agreement on what constitutes death? And we are now having trouble with the beginning of human life, so much more complicated. Why is that so much more complicated to reach consensus on?

SARAH VARNEY: There has not been the same effort to really define what constitutes the beginning of life. I mean, in some extent, this is because there’s a real religious belief based on when life begins. And really, perhaps medicine and science is not necessarily the best place to turn to even ask that question.

So I spoke with David Magnus. He’s on this committee that is determining and refining the notion of brain death. He’s a bioethicist and the director of the Stanford Center for Biomedical Ethics. And let’s take a listen to what he said about how you define when life begins and even when life ends.

DAVID MAGNUS: Biological occurrences are processes, not events. It means that deciding where you want to draw lines is a decision to be made, not something to be discovered. And so we have to decide where lines make the most sense.

SARAH VARNEY: So what Magnus is essentially saying is that death and even conception are not moments in time. And it’s a complicated process.

DAVID MAGNUS: When people talk about beginning at the time of conception, do they mean when the sperm first comes in contact with the zona pellucida of the egg cell? Is it when that actual nucleic material, that DNA, actually starts to play a role, which isn’t till a few cell divisions in? Somewhere in that process, we call that conception.

SARAH VARNEY: Magnus and some of the other bioethicists that I spoke to in reporting the story would say that biology really suggests that conception is just too early in the process to even consider that someone, that a life, is a person. Let’s hear David Magnus again.

DAVID MAGNUS: The fact that so many very early embryos are lost without women even knowing they’re pregnant is informative and is relevant to figuring out where to draw the line.

SARAH VARNEY: And Magnus really says asking doctors what is life or what is death may actually just miss the point that medicine can’t really answer that question, when does a person begin or end, because those are really metaphysical issues. And this gets really interesting.

There are people who study medical ethics, including Ben Sarbey– he’s a doctoral candidate at Duke University’s department of philosophy. And when I was speaking with him, he offered me this example called the paradox of the heap. And it’s essentially a thought experiment where a person places grains of sand one after another. And the philosophical quandary is this– when does that collection of sand become more than itself, a pile? This is a direct parallel to the debate over abortion and also the right to die.

So Sarbey would say that many things count as life. A sperm counts as life. A person in a persistent vegetative state counts as life. But does that constitute a person that the government should be protecting?

IRA FLATOW: Yeah, when Justice Alito wrote the majority decision overturning Roe in June, he did not incorporate the advice of medical professionals like you’re talking about. And unlike the original Roe decision, which weighed medical guidance, it’s now up to the states to determine when human life begins. So what kinds of laws have states passed as a result?

SARAH VARNEY: There are a number of Republican-led states, including Missouri, Kentucky, Arkansas, Oklahoma, and others, that have laws that have declared that life begins at fertilization, so this moment of conception that Magnus says is actually elusive. And those laws have really profound legal implications. So there can be wrongful death lawsuits on behalf of the estate of the embryo or fetus by a disgruntled ex-partner or family against physicians and women who even end a pregnancy or even miscarry.

In Kentucky, for example, the law outlawing abortion uses medically inaccurate and really morally potent terms to define pregnancy as, quote, “the human female reproductive condition of having a living unborn human being within her body, throughout the entire embryonic and fetal stages of the unborn child.” Now, in that sentence, there are many inaccurate terms, “a living unborn human being,” for instance.

Now, several other states, including Georgia, they’ve adopted measures that equate life with the point at which an embryo’s nascent cardiac activity– that’s when these sort of beginning electrical impulses start flickering, which is around six weeks of gestation. And these laws really mischaracterize the flickering electrical impulses detectable at that stage as a heartbeat. And recently, in fact, in Georgia, the Department of Revenue announced that, quote, “any unborn child with a detectable human heartbeat,” by which they mean around six weeks, can actually be claimed now as a dependent on your taxes.

IRA FLATOW: You know, Sarah, we started off this conversation talking about the end of life, which feels like it comes with a different set of issues than the beginning of life. But there’s some striking parallels in the debates around aid in dying legislation. Tell me more about that.

SARAH VARNEY: There is ample connective tissue between the legal arguments surrounding abortion and the right to die. So for instance, the legal standard in Dobbs, that there is no right to abortion in the federal Constitution, which is what the Supreme Court just said, and that states can decide this issue on their own, was the same exact rationale that was used in 1997 when the Supreme Court said that terminally ill people did not have a constitutional right to doctor-assisted suicide.

And there were other members of the court’s conservative bloc that overturned Roe that have also been heavily involved in arguing against the right to die. That includes Justice Neil Gorsuch, who actually wrote a book in 2017 called The Future of Assisted Suicide and Euthanasia. And that was advertised as providing the most comprehensive argument against its legalization that was ever published. And supporters of the Dobbs decision agree that it could provide a means for challenging states like Oregon, which was the first state to pass a right to die law in 1997.

Jim Bopp, who is the chief lawyer for the National Right to Life Committee, who has been central in the efforts to overturn abortion, he also said that both abortion and medical aid in dying endanger society. Jim Bopp, interestingly enough, is also on that committee right now that is helping to refine the definition of death. And he very much opposes this notion of brain death and allowing hospitals and families to essentially, quote, “pull the plug” on their family members.

IRA FLATOW: Sarah, always interesting stuff. Thank you for taking time to be with us today.

SARAH VARNEY: Oh, thank you so much, Ira.

IRA FLATOW: Sarah Varney, senior correspondent for Kaiser Health News, based in Monterey, Massachusetts. And you can read Sarah’s full story by heading over to our website, sciencefriday.com/lifeanddeath.

Copyright © 2022 Science Friday Initiative. All rights reserved. Science Friday transcripts are produced on a tight deadline by 3Play Media. Fidelity to the original aired/published audio or video file might vary, and text might be updated or amended in the future. For the authoritative record of Science Friday’s programming, please visit the original aired/published recording. For terms of use and more information, visit our policies pages at http://www.sciencefriday.com/about/policies/.


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