The ACLU filed an amicus curiae brief in this lawsuit which concerns the picketing and invasion of the Planned Parenthood of Contra Costa's Walnut Creek clinic by a group of protestors who identified themselves as Catholics United for Life - an anti-abortion group. The protestors were waiting when the clinic opened at 8 am and disrupted operations until 10 am that day, May 16, 1981. Because the clinic had prior experience with harassment, it kept its doors locked. The protestors gained entry to the clinic by falsely claiming that a woman was in need of a pregnancy test, and proceeded to occupy examination and surgical rooms, refusing to leave. Around 10 am, they were arrested, and charged with eight counts of trespass and three counts of battery (a picket had allegedly hit a clinic employee).

In September 1981, the defendants claimed that it was necessary to their cases to subpoena all Planned Parenthood medical and financial records. It was at this point that the ACLU stepped in. The defendants based their defense on the idea that any actions taken (including storming the abortion clinic and assaulting its staff) are jusfified to prevent the so-called "murder" of abortion. The ACLU argued that the use of this "necessity" defense transforms a simple criminal prosecution into a full-blown probe of the legality and morality of abortion, and claims that a criminal act is justified to interfere with the exercise of a constitutional right. The cases also sought to reopen issues closed by Roe v. Wade, namely the definition of what constitutes "life."

The protestors conviction was upheld by the court, and a transfer to the Court of Appeals was denied. Each protestor was required to either pay $1,000, or spend ten days in jail.