The Trump administration has proposed a shift in rules that would make it “nearly impossible” for Americans to sue for housing discrimination caused by algorithms, according to tech scholars and civil rights groups.

Absolving companies of wrongdoing when algorithms are involved could have a major effect on the housing market, which often relies on automation – in the form of background checks, credit score analysis, and analyzing an applicant’s history – to decide whether to rent or sell someone a home.

The new ruling would raise the bar for legal challenges against housing discrimination, making cases brought against landlords and lenders less likely to succeed.

It does this through tweaking the interpretation of the “disparate-impact” standard of the 1968 Fair Housing Act, which permits the use of statistical analysis to identify patterns of discrimination and prohibits discriminatory conduct, even if the conduct does not have “discriminatory intent”.

Representatives from New York University, the AI Now Institute, the University of Maryland, non-profit Center on Race Inequality, and the Law and Princeton encouraged the administration to withdraw the proposed rule in the lengthy letter issued on Friday.

“This change is part of a long arc of retrenching America’s promise of equality,” Rashida Richardson, the director of policy research at the AI Now Institute said. “Over the past few decades we have seen an intentional chipping away at the few civil rights protection standards we have, and you are seeing this expedited under the Trump administration.”

Under the Department of Housing and Urban Development’s (HUD) new rules, businesses would be shielded from liability when their algorithms are accused of bias through three different loopholes:

When the algorithm in question is vetted by a “neutral third party”.

When the algorithm itself was created by a third party.

If an algorithm used did not use race or a proxy for it in the computer model.

In the letter, groups in opposition to the change noted many pieces of data can be proxies for race – discriminating by a zip code, for example, can enable a racial bias. The rule would give “unprecedented deference” to mortgage lenders, landlords, banks, insurance companies, and others in the housing industry, the letter said.

“With this proposed rule, the agency is taking extraordinary steps to dismantle the very protections and tools that counteract the often covert policies and practices that disparately impact on communities of color,” the letter said.

The proposed changes come as the gap between black and white homeownership among young adults in the US is at its widest since the 1940s, when housing discrimination was legal.

HUD did not immediately respond to request for comment, but housing secretary Ben Carson recently wrote in an op-ed that the current interpretation of the law “does not reflect common sense” and under new rules plaintiffs would have to “show a robust causal link between the challenged policy and the disparity that is not established by statistical imbalances alone”.

“Ultimately, these changes will lead to more innovation and an increase of lower-cost housing and related services,” he said.

The comment period for the ruling officially ended Friday, but advocacy groups are making an effort to build public awareness and submit more comments before a ruling is made.