Forty years after the U.S. Supreme Court issued its Roe v. Wade decision, a leading pro-life legal expert believes the decision has never been more vulnerable to being overturned.

In his new book, Abuse of Discretion: The Inside Story of Roe v. Wade, Clark Forsythe, senior legal counsel at Americans United for Life, details what he uncovered in examining the private papers of the justices, their case files, and oral arguments. After 20 years of research, Forsythe found that:

The justices decided to hear Roe under a misunderstanding that it concerned state criminal prosecutions, not a constitutional right to abortion.

They arbitrarily expanded fetal viability from 12 weeks to 28 weeks with little discussion or medical knowledge.

The Court's majority relied heavily on popular, but unproved, '70s-era evidence that there was an urgent need for population control in the United States.

Since Roe, there have been 50 million abortions in the United States. Currently, there are about 1 million per year. But public opinion has slowly been shifting toward ending abortion on demand. The 2013 Gallup poll showed that since 1995, more Americans than ever consider themselves pro-life. Overall the nation remains very evenly divided on abortion. Gallup reports that there is a difference of only 3 percentage points between pro-life and pro-choice (48 percent vs. 45 percent).

Timothy C. Morgan, CT senior editor of global journalism, recently interviewed Forsythe about his book, which The Wall Street Journalsaid "provides a cautionary tale about the political and constitutional hazards of unnecessarily broad Supreme Court decisions."

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