"The few prosecutions that were instituted faced jurors unwilling to convict abortionists and judges unwilling to impose severe sentences. Anti-abortion advocates complained that "even the most outrageous abortionist" could not be convicted in a jury trial.
One juror refused to convict a well-known abortionist because there was "nobody in Schuykill County that the doctor hasn't helped." Half the abortionists convicted in New York between 1925 and 1950 were sentenced only to probation. Dr. Milan Vuitch, a prominent physician-abortionist, was arrested sixteen times for openly running an abortion clinic in Washington, D.C. but never went to jail.
Even abortionists convicted and sentenced to prison at trial often escaped legal sanction. Some appellate judges placed extraordinarily high burden of proof on the state to establish that insufficient medical grounds existed for the abortion. After pointing out that, "the defendant in this case was a doctor with substantial experience and background." the California court in People v. Ballard overturned a conviction for illegally performing an abortion because the jury was not told that "there is a presumption of necessity in the case of an abortion by a licensed physician." In times and places not noted for their solicitude for the due process rights of criminal suspects, a significant number of convictions for illegal abortion were reversed on appeal for constitutional "technicalities," most notably entrapment. Some executives used clemency to keep abortionists on the street. A New York campaign against illegal abortion during the first decade of the twentieth century came to a dismal conclusion when the only three abortionists convicted were immediately pardoned by the governor."
http://www.pinn.net/~sunshine/book-sum/rethink.html