The most radical abortion law in the US has gone into effect, despite legal efforts to block it.

A near-total abortion ban in Texas empowers any private citizen to sue an abortion provider who violates the law, opening the floodgates to harassing and frivolous lawsuits from anti-abortion vigilantes that could eventually shutter most clinics in the state.

“Abortion access will be thrown into absolute chaos,” says Amanda Williams, executive director of the abortion support group the Lilith Fund, a plaintiff in the suit that challenged the law. “Unfortunately, many people who need access the most will slip through the cracks, as we have seen over the years with the relentless attacks here in our state.

“It is unbelievable that Texas politicians have gotten away with this devastating and cruel law that will harm so many.”

Senate Bill 8, ushered through the Republican-dominated Texas legislature and signed into law by the Republican governor, Greg Abbott, in May, bars abortion once embryonic cardiac activity is detected, which is around six weeks, and offers no exceptions for rape or incest. Texas is the first state to ban abortion this early in pregnancy since Roe v Wade, and last-minute efforts to halt it through an appeal to the US supreme court by Tuesday did not succeed.

While a dozen other states have passed similar so-called “heartbeat” bills, they have all been blocked by the courts. The Texas version is novel in that it is intentionally designed to shield government officials from enforcement, and thus make legal challenges more difficult to secure. It instead incentivizes any private citizen in the US to bring civil suit against an abortion provider or anyone who “aids or abets” the procedure.

The law “immediately and catastrophically reduces abortion access in Texas”, say state abortion providers, and will probably force many abortion clinics to ultimately close. It will prevent the majority of Texas women (85%) from accessing abortion care, as most aren’t aware they are pregnant as early as six weeks.

Joe Biden condemned the new law and reaffirmed the White House’s support for abortion rights. “This extreme Texas law blatantly violates the constitutional right established under Roe v Wade and upheld as a precedent for nearly half a century,” Biden said in the statement.

Planned Parenthood, which operates 11 clinics in the state, and Whole Woman’s Health clinics told the Guardian they would comply with the extreme law despite the fact that it is contrary to their best medical practices. In the days leading up to the law’s enactment, Texas clinics say they have been forced to turn away patients who need abortion care at the law’s cutoff point this week and into the near future.

Some abortion physicians in Texas have opted to discontinue offering services, choosing to forgo the potential risk of frivolous and costly lawsuits. For instance, most of the physicians across the four Whole Woman’s Health clinics in Texas will not continue care to prevent jeopardizing their livelihoods, said the clinic founder, Amy Hagstrom Miller.

“We are all going to comply with the law even though it is unethical, inhumane, and unjust,” Dr Ghazaleh Moayedi, a Texas abortion provider and OB-GYN, said. “It threatens my livelihood and I fully expect to be sued. But my biggest fear is making sure the most vulnerable in my community, the Black and Latinx patients I see, who are already most at risk from logistical and financial barriers, get the care they need.”

The law will force most patients to travel out of state for care, increasing the driving distance to an abortion clinic twentyfold – from an average of 12 miles to 248 miles one-way, nearly 500 miles round-trip, the Guttmacher Institute found. And that is only if patients have the resources to do so, including time off work, ability to pay for the procedure, and in some cases childcare.

Providers and abortion fund support groups – who help finance travel, lodging, and direct service for low-income women through donations – have spent months scrambling to coordinate with out-of-state clinics, including in New Mexico and Colorado, to ensure patients receive timely care when SB8 goes into effect. Last year, the state was offered a glimpse of what would happen if abortion care ceased: when the state barred most abortion procedures amid the Covid-19 pandemic in March 2020, the number of patients who traveled out of state for care jumped nearly 400%.

Many abortion-seeking women are expected to be delayed until later in pregnancy and others will be forced to carry pregnancy to term or try to end their pregnancies without medical oversight, abortion providers caution. As with most abortion restrictions, low-income women and women of color will bear the greatest burden under SB8.

Physicians are not the only ones that could be targeted under SB8: a breathtakingly wide range of people and groups, including clinic nurses, abortion fund workers, domestic violence and rape crisis counselors, or even a family member who offers a car ride to the clinic could now face suit from strangers. Those who sue can collect a minimum of $10,000 if they win, but if providers are legally successful they cannot recoup any legal payment. The law, say providers, will spur abortion “bounty hunters”.

The law’s radical legal provision is the first of its kind in the country.

The state’s major anti-abortion lobby group, Texas Right to Life, have already helped empower anti-abortion activists to enforce the law by creating a website that invites “whistleblowers” to report violations of SB8. (In response, pro-choice advocates have flooded the digital entry forms with satirical information.)

Abortion providers, funds, and clergy members, represented by the Center for Reproductive Rights, Planned Parenthood Federation of America, and the American Civil Liberties Union, filed suit against SB8 in July, writing that the law would “create absolute chaos in Texas and irreparably harm Texans in need of abortion services.”

A preliminary injunction hearing was originally set for Monday 30 August in federal court. However, the largely conservative fifth circuit court of appeals cancelled the hearing on Sunday afternoon and denied the plaintiffs’ request to allow the district court to block the law. Providers then appealed to the US supreme court for emergency relief.

But the court failed to act before the law took effect on Wednesday, allowing it to proceed. While the nation’s high court, which now holds a strong anti-choice contingent, plans to consider a Mississippi 15-week ban that could test Roe v Wade during the next term, its lack of action in the Texas case signals the possible early unraveling of Roe.

Texas is already one of the most difficult states in the US in which to access abortion due to a slew of state laws pushed by the Republican-dominated legislature over the past decade, including a 24-hour waiting period, a 20-week abortion ban, restrictions on telemedicine, and a prohibition on private and public insurance. It is home to the highest number of abortion deserts – cities in which an abortion-seeking patient must travel at least 100 miles for care – in the country.

Following the passage of a 2013 multi-part law known as House Bill 2, roughly half of the state’s abortion clinics shuttered – dropping from 40 to less than 20. While the law was eventually struck down by the US supreme court in 2016, many clinics were unable to reopen. Large swaths of the state – including the Panhandle and west Texas – are without an abortion clinic, forcing women to travel great distances for care.