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Natural Law

Secular Natural Law



The school of natural law known as secular natural law replaces the divine laws of God with the physical, biological, and behavioral laws of nature as understood by human reason. This school theorizes about the uniform and fixed rules of nature, particularly human nature, to identify moral and ethical norms. Influenced by the rational empiricism of the seventeenth-and eighteenth-century Enlightenment thinkers who stressed the importance of observation and experiment in arriving at reliable and demonstrable truths, secular natural law elevates the capacity of the human intellect over the spiritual authority of religion.



Many secular natural law theorists base their philosophy upon hypotheses about human behavior in the state of nature, a primitive stage in human evolution before the creation of governmental institutions and other complex societal organizations. In the state of nature, John Locke wrote, human beings live according to three principles—liberty, equality, and self-preservation. Because no government exists in the state of nature to offer police protection or regulate the distribution of goods and benefits, each individual has a right to self-preservation that he or she may exercise on equal footing with everyone else.

This right includes the liberties to enjoy a peaceful life, accumulate wealth and property, and otherwise satisfy personal needs and desires consistent with the coterminous liberties of others. Anyone who deprives another person of his or her rights in the state of nature, Locke argued, violates the principle of equality. Ultimately, Locke wrote, the state of nature proves unsatisfying. Human liberty is neither equally fulfilled nor protected. Because individuals possess the liberty to delineate the limits of their own personal needs and desires in the state of nature, greed, narcissism, and self-interest eventually rise to the surface, causing irrational and excessive behavior and placing human safety at risk. Thus, Locke concluded, the law of nature leads people to establish a government that is empowered to protect life, liberty, and property.

Lockean JURISPRUDENCE has manifested itself in the decisions of the Supreme Court. In Powell v. Pennsylvania, 127 U.S. 678, 8 S. Ct. 1257, 32 L. Ed. 253 (1888), Justice STEPHEN J. FIELD wrote that he had "always supposed that the gift of life was accompanied by the right to seek and produce food, by which life can be preserved and enjoyed, in all ways not encroaching upon the equal rights of others." In another case the Supreme Court said that the "rights of life and personal liberty are the natural rights of man. To secure these rights … governments are instituted among men" (U.S. v. Cruikshank, 92 U.S. 542, 2 Otto 542, 23 L. Ed. 588 [1875]).

In the spirit of Lockean natural law, the Fifth and Fourteenth Amendments to the Constitution prohibit the government from taking "life, liberty, or property without due process of law." The concept of "due process" has been a continuing source of natural law in constitutional jurisprudence. If Lockean natural law involves theorizing about the scope of human liberty in the state of nature, constitutional natural law involves theorizing about the scope of liberty protected by the Due Process Clauses of the Fifth and Fourteenth Amendments.

On their face the Due Process Clauses appear to offer only procedural protection, guaranteeing litigants the right to be informed of any legal action being taken against them and the opportunity to be heard during an impartial hearing where relevant claims and defenses may be asserted. In the 200 years following the writing of the Constitution, however, federal courts interpreted the Due Process Clauses to provide substantive protection against ARBITRARY and discriminatory governmental encroachment of fundamental liberties. Similar to the rational empiricism by which Enlightenment thinkers identified HUMAN RIGHTS in the state of nature, federal judges have identified the liberties protected by the Due Process Clauses through a reasoned elaboration of the Fifth and Fourteenth Amendments.

The federal judiciary has described the liberty interest protected by the Due Process Clauses as an interest guaranteeing a number of individual freedoms, including the right to personal autonomy, bodily integrity, self-dignity, and self-determination (Gray v. Romeo, 697 F. Supp. 580 [1988]). The word liberty, the Supreme Court stated, means something more than freedom from physical restraint. "It means freedom to go where one may choose, and to act in such manner … as his judgment may dictate for the promotion of his happiness … [while pursuing] such callings and avocations as may be most suitable to develop his capacities, and give to them their highest enjoyment" (MUNN V. ILLINOIS, 94 U.S. 113, 4 Otto 113, 24 L. Ed. 77 [1876] [Field, J., dissenting]).

The full breadth of constitutional liberty, the Supreme Court has said, is best explained as a rational continuum safeguarding every facet of human freedom from arbitrary impositions and purposeless restraints (Poe v. Ullman, 367 U.S. 497, 81 S. Ct. 1752, 6 L. Ed. 2d 989 [1961]). The government may not intrude upon this liberty unless it can demonstrate a persuasive countervailing interest. However, the more that the U.S. legal system cherishes a particular freedom, the less likely a court is to enforce a law that infringes upon it.

In this regard the Supreme Court has identified certain fundamental rights that qualify for heightened judicial protection against laws threatening to restrict them. This list of fundamental rights includes most of the specific freedoms enumerated in the BILL OF RIGHTS, as well as the FREEDOM OF ASSOCIATION; the right to vote and participate in the electoral process; the right to marry, procreate, and rear children; and the right to privacy. The right to privacy, which is not expressly enumerated anywhere in the Constitution, guarantees the freedom of adults to use BIRTH CONTROL (GRISWOLD V. CONNECTICUT, 381 U.S. 479, 85 S. Ct. 1678, 14 L. Ed. 2d 510 [1965]) and the right of women to terminate their pregnancy before the fetus becomes viable (ROE V. WADE, 410 U.S. 113, 93 S. Ct. 705, 35 L. Ed. 2d 147 [1973]).

During the 1990s the right to privacy was enlarged to recognize the right of certain terminally ill or mentally incompetent persons to refuse medical treatment. In Cruzan v. Missouri Department of Health, 497 U.S. 261, 110 S. Ct. 2841, 111 L. Ed. 2d 224 (1990), the Supreme Court ruled that a person who is in a persistent vegetative state, marked by the absence of any significant cognitive abilities, may seek to terminate life-sustaining measures, including artificial nutrition and hydration equipment, through a parent, spouse, or other appropriate guardian who demonstrates that the incompetent person previously expressed a clear desire to discontinue medical treatment under such circumstances.

The Court of Appeals for the Ninth Circuit later cited Cruzan in support of its decision establishing the right of competent but terminally ill patients to hasten their death by refusing medical treatment when the final stages of life are wrought with pain and indignity (Compassion in Dying v. Washington, 79 F.3d 790 [9th Cir. 1996]). However, the Court of Appeals for the Second Circuit ruled that physicians possess no due process right to assist terminally ill patients in accelerating their death by prescribing a lethal dose of narcotics (Quill v. Vacco, 80 F.3d 716 [2d Cir. 1996]). Similarly, in a notorious case involving Dr. JACK KEVORKIAN, the Michigan Supreme Court ruled that patients have no due process right to physician-assisted suicide (People v. Kevorkian, 447 Mich. 436, 527 N. W. 2d 714 [1994]).

In the Cruzan decision, the manner in which the Supreme Court recognized a qualified right to die reflects the Enlightenment tradition of secular natural law. Where Locke inferred the inalienable rights of life, liberty, and property from observing human behavior, the Supreme Court said in Cruzan that "a Constitutionally protected liberty interest in refusing unwanted medical treatment may be inferred from our prior decisions."

For example, in Jacobson v. Massachusetts, 197 U.S. 11, 25 S. Ct. 358, 49 L. Ed. 643 (1905), the Supreme Court protected the constitutional right of a person to decline a smallpox vaccination that was required by state law. In Washington v. Harper, 494 U.S. 210, 110 S. Ct. 1028, 108 L. Ed. 2d 178 (1990), the Court ruled that the liberty interest guaranteed by the Due Process Clauses prohibits the government from compelling prisoners to take antipsychotic drugs. These cases, as well as others, the Supreme Court reasoned in Cruzan, establish that all U.S. citizens have a general right to refuse unwanted medical treatment, which includes the specific right of certain mentally incompetent and terminally ill persons to hasten their death.

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