The new law in Texas effectively banning most abortions has ignited widespread controversy and debate, in part because of the mechanism it uses to enforce the restrictions: deputizing ordinary people to sue those involved in performing abortions and giving them a financial incentive to do so.

The law establishes a kind of bounty system. If these vigilante plaintiffs are successful, the law allows them to collect cash judgments of $10,000 — and their legal fees — from those they sue. If they lose, they do not have to pay the defendants’ legal costs.

The Supreme Court declined to stop the legislation from taking effect, and so far, no one has brought a suit against an abortion provider because clinics in the state have chosen to abide by the law, which effectively bars abortions starting around the sixth week of pregnancy.

The enforcement provision has generated backing from those seeking to limit abortion rights but confusion and criticism among supporters of abortion rights.

“When the law first came out and I was reading it, I thought I was missing something,” said Mary Ziegler, a professor at the Florida State University College of Law who specializes in the history of reproductive law. “It almost seemed like anyone could sue anyone — and that didn’t seem right. But it was. It really is that extraordinary.”

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According to Ms. Ziegler, the notion of using civil lawsuits to curb or stop abortions first emerged in the early 1990s, when a Texas pastor named Mark Crutcher created a program called Spies for Life that published manuals showing people how to use the legal system to go after abortion clinics and providers. In 1999, Louisiana passed its own law giving women who had abortions the right to sue their providers.