In California, the lawsuits are mounting — middle-aged men, saying they were sexually assaulted as children by a Boy Scout leader or a priest. A woman, now in her late 30s, detailing how she was allegedly assaulted in a center for foster children. A man who said he was abused while volunteering with the Salvation Army.

At least 750 of those lawsuits filed since January 2020 are against Catholic dioceses, and more than 800 people are in the process of filing to beat a Dec. 31 deadline, according to lawyers involved in the cases.

The year-end date marks the close of the state’s three-year “lookback window,” which allows plaintiffs to file civil suits for childhood sexual abuse no matter how long ago the alleged events took place.

Now, facing hundreds of lawsuits, a group of Catholic bishops is taking those challenges to the nation’s highest court. Saying they faced “potentially ruinous liability,” the bishops last month asked the U.S. Supreme Court to declare the California lookback window unconstitutional.

“Review is critical now, before the Catholic Church in the largest state in the union is forced to litigate hundreds or thousands of cases seeking potentially billions of dollars in retroactive punitive damages,” according to the petition, which was first reported by the Catholic News Agency.

California created its new lookback window in 2019 under Assembly Bill 218, authored by then-Assemblymember Lorena Gonzalez, a San Diego Democrat.

The bill opened a three-year period, from 2020 to 2022, that permitted complainants to file sexual abuse claims that exceeded the statute of limitations.

The law allows people younger than 40 to file complaints without any extra steps. Complainants older than 40 must obtain, through an attorney, a mental health evaluation that finds “there is a reasonable basis to believe that the plaintiff had been subject to childhood sexual abuse.”

In 2002, the state passed a similar law creating a year-long window for people to file such claims. More than 850 people sued the Catholic Church the following year, and another 150 sued other religious institutions and the Boy Scouts of America. The Catholic Church paid out more than $1 billion to settle claims, according to the bishops’ petition to the U.S. Supreme Court.

Multiple dioceses sold “vast swaths” of church property in the 2000s, the petition states. Some exhausted or relinquished their lawsuit insurance, and the church believed at the time that the matter was over.

“That assurance proved to be false,” the bishops wrote.

Across the country, such lookback windows have faced and survived multiple legal challenges at the state level. Actor Bill Cosby, accused of more than 50 sexual assaults over decades, has challenged them in California and New Jersey. Prince Andrew’s initial challenge to New York’s “lookback window” failed to persuade a judge in January to throw out his case.

Los Angeles attorney Paul Mones, who is representing at least 75 people suing the Catholic Church and dozens more suing other institutions, said he expects “a flurry of filings” in the last 60 days of the year before the lookback window expires.

Among his cases, Mones said, were people suing the Boy Scouts of America, private schools, public schools, the Salvation Army, Big Brothers Big Sisters and the Boys & Girls Clubs of America.

“There are few institutions that serve youth that do not have a history of having perpetrators in them who harm children,” Mones said.

The U.S. Supreme Court has struck down a previous California lookback window, but that was specific to criminal prosecution.

In that 2003 case, Stogner vs. California, the high court ruled 5-4 that allowing California to charge someone criminally with child sex abuse after the statute of limitations had expired “inflicted punishment for past criminal conduct that … did not trigger any such liability.”

The lawsuits during the current window have been targeted at both religious and secular institutions. In California, more than 200 women and men have sued an El Monte children’s center, alleging abuse between 1988 and 2001.

In Sacramento, two brothers have sued the Capital Christian Center, alleging that they and three other former students were abused sexually in the early 1980s.

Rick Simons, a plaintiff’s attorney managing the cases against the Catholic Church in Northern California, said his oldest case dates to the early 1960s. That litigant and others like him didn’t sue during California’s 2003 lookback window because “he wasn’t ready,” Simons said.

“One year is just not enough time for some folks to process stuff,” Simons said. “This time, maybe the parents are mostly gone. Many more people are sober.”

“This was news in 2002 and 2003, that Catholic priests were engaged in systematic abuse. People hadn’t heard it on that scale,” he added.

The abuse cases against the Catholic Church during the current lookback window have been divided into three consolidated cases across the state: Northern California, San Diego and Los Angeles. In Northern California, plaintiff’s attorneys said more than 200 people have already filed suit, and another 800 are in the process of filing.

In San Diego, 80 people have filed suit, and in Los Angeles, 473 people have sued.

“The (bishops’) petition is an attempt to invalidate the law and a disingenuous slap in the face to victims who have yet to come forward,” said Mike McDonnell, spokesperson for the group Survivors Network for those Abused by Priests, or SNAP.

“It’s concerning to us because it’s not a thing of the past, it is a thing of the present and it is absolutely a thing of the future.”

McDonnell said the sexual abuse claims test not just the financial resources of the Catholic Church and its dioceses, but the insurers that cover them.

Insurers have expressed concern over the reopened statute of limitations and their financial exposure to costs far higher than they anticipated when they originally issued policies for an organization, whether it’s a church or a Boy Scout troop.

In 2019 alone, 14 states amended their laws to allow more time for claims of child sexual abuse, and at least eight states reopened the window for abuse claims that had exceeded the statute of limitations.

Nationwide, lookback windows have typically led to thousands of lawsuits. In New Jersey, for instance, more than 1,200 sexual abuse lawsuits were filed between December 2019, when the state’s lookback window opened, and October 2021, when it closed, according to the Associated Press.

About two-thirds of those New Jersey lawsuits named religious institutions. Lawsuits against schools represented about 14% and about 9% named the Boy Scouts.

Bill Donohue, president of the New York-based Catholic League, said in a statement that a focus on the Catholic Church in child sex abuse legislation and litigation is “anti-Catholic bigotry.”

“It is a myth to maintain that the Catholic Church has a monopoly on the sexual abuse of minors: it exists in every institution where adults interact with youngsters,” Donohue said.

“The Catholic Church in California has twice dealt with this issue. It should not be subjected to another round of lawsuits.”

California Catholic churches have paid among the highest dollar amounts for sex abuse settlements of any state, according to a list of settlements compiled by the website Bishop Accountability.

The Los Angeles diocese paid $660 million to settle hundreds of abuse claims in 2007, and that same year, the San Diego diocese filed for bankruptcy and paid 144 people a total of $198 million. Those are the two highest settlements made by the Catholic Church in the U.S.

Bankruptcy is a real fear for the churches involved in this litigation, said Jeff Anderson, a Minneapolis-based attorney with an office in Los Angeles who represents child sex abuse claimants suing the Catholic Church.

“They are among the most frequent offenders, so yes, they are the most exposed [financially],” Anderson said.

Anderson said the church is banking on the 6-3 conservative majority on the Supreme Court, as well as the justices’ own religious affiliations — six justices are Catholic, though one, Sonya Sotomayor, is part of the court’s liberal minority.

“I think that’s the only thing they can bank after,” Anderson said. “This writ is really the Hail Mary pass to the Catholic court.”

Nigel Duara is a reporter with CalMatters.