On this date, January 9, in the year 1979, the U.S. Supreme Court struck down a Pennsylvania law that subjected abortion providers to criminal sanctions if they failed to attempt to preserve the life of a fetus when there is "sufficient reason to believe that the fetus may be viable" or when the fetus “is viable.”

The Abortion Control Act was passed by the Pennsylvania Legislature, over the Governor's veto, in the year following the Supreme Court's decision in Roe v. Wade, 410 U. S. 113 (1973).  The law required a doctor performing an abortion to take whatever actions deemed necessary to protect the life of a fetus if the doctor determined that the fetus is or may be viable (except when the life of the mother was in danger).  The statute subjected physicians with the possibility of being charged criminally with homicide should it be determined that there was a sufficient reason to believe that a fetus might have been viable.  This law was challenged by a medical director at a Pennsylvania Planned Parenthood affiliate in Colautti v.  Franklin.

The Supreme Court found the Pennsylvania statute unconstitutional because it was to vague and ambiguous.   According to the Supreme Court, a valid criminal statute is required to "give a person of ordinary intelligence fair notice that his contemplated conduct is forbidden."  The Court found the Pennsylvania law was not clear in defining the meaning of "may be viable" and questioned whether the standard was based upon the physician's personal experience and judgement or, rather, upon the "perspective of a cross section of the medical community or a panel of experts."

In finding the Pennsylvania criminal statute unconstitutional the Supreme Court held as follows:

The perils of strict criminal liability are particularly acute here because of the uncertainty of the viability determination itself.  As the record in this case indicates, a physician determines whether or not a fetus is viable after considering a number of variables: the gestational age of the fetus, derived from the reported menstrual history of the woman; fetal weight, based on an inexact estimate of the size and condition of the uterus; the woman's general health and nutrition; the quality of the available medical facilities; and other factors.  Because of the number and the imprecision of these variables, the probability of any particular fetus' obtaining meaningful life outside the womb can be determined only with difficulty.  Moreover, the record indicates that even if agreement may be reached on the probability of survival, different physicians equate viability with different probabilities of survival, and some physicians refuse to equate viability with any numerical probability at all.  In the face of these uncertainties, it is not unlikely that experts will disagree over whether a particular fetus in the second trimester has advanced to the stage of viability.  The prospect of such disagreement, in conjunction with a statute imposing strict civil and criminal liability for an erroneous determination of viability, could have a profound chilling effect on the willingness of physicians to perform abortions near the point of viability in the manner indicated by their best medical judgment.     

Sources and more information:

Colautti, Secretary of Welfare of Pennsylvania, et al.   v.   Franklin et al.  439 U.S. 379 (1979)

Colautti v. Franklin - A Specific Definition Of Viability, jrank.org