Lennard Davis is distinguished professor of liberal arts and sciences at the University of Illinois at Chicago and author of "Enabling Acts: The Hidden Story of How the Americans With Disabilities Act Gave the Largest U.S. Minority Its Rights." David Perry is a journalist and senior academic adviser to the history department at the University of Minnesota.

The Americans With Disabilities Act of 1990 is perhaps the most wide-ranging civil rights act in the world. After decades of political struggle by disability rights activists and their allies, the ADA gave new rights to one-fifth of the population. It was a proud bipartisan accomplishment, passed by huge majorities in a Democratic-led Congress and signed by a Republican president.

But now, in this era of extreme partisanship, the future of the ADA is under threat. On a strict party-line vote, the House Judiciary Committee recently advanced legislation that would essentially make the ADA optional.

The bill, misleadingly called the ADA Education and Reform Act, is about neither education nor reform. Instead, it would make the ADA much harder to enforce, taking away the major motivation that businesses had for complying: fear of being sued.

If a business discriminates against people with disabilities under current law, a complainant could either bring a civil suit against the business or go directly to the Justice Department for action. This hard-nosed approach has made businesses think twice before refusing to comply with the ADA.

Opponents of the law have long argued that it is anti-business, but in fact protections for business have always been part of the equation. No one expects the "mom-and-pop" diner to have the same resources as big corporate chains such as Cracker Barrel, so business-friendly Republicans who helped craft the ADA provided several ways to avoid harming smaller enterprises. If complying with the law would cause "undue hardship" to the business, owners could opt out of the requirements of the law.

The proposed legislation offers a new system for disability rights: do nothing until someone notices, then stall for at least 120 days. If the bill becomes law of the land, business owners would have no incentive to preemptively build accessibility into their business model. They could just wait until someone needed access, shrug, deny access and address it months later. What about a person who needed an accessible hotel, restaurant or restroom immediately? What recourse would he or she have?

Those who support the proposed law often argue that the ADA mostly benefits a handful of lawyers who profit from frivolous lawsuits. Clint Eastwood once waved off a lawsuit against a resort he owns in California, describing the suit as based on people "lying to get money." Others have similarly argued that businesses should be given a timeout period to comply with the law after being told about violations.

But there is a major flaw to this logic: No one should arrive at a hotel, find out it is inaccessible and then have to wait months to be allowed inside. And when it comes to frivolous lawsuits, state bar associations are already well equipped to impose sanctions on unscrupulous lawyers through provisions included in the ADA.

The history of disability rights in this country is marked by many challenges yet to be resolved. But it is also marked by major victories such as the ADA. Activists, policy experts and politicians came together in a bipartisan manner to pass the law and redesign society. Before the ADA, much of the country was inaccessible to people with disabilities. But having added a host of accommodations, including curb cuts, ramps, closed captioning, accessible public transportation and American Sign Language interpreters, we have made unbelievable progress, and it's thanks to leaders from across the political spectrum.

Such a feat could never happen today. The partisanship is just too intense. But that doesn't mean our fractured Congress should be allowed to disrupt almost three decades of making the United States better. We can't let a few bad lawyers and a few stingy business owners resurrect barriers we've worked so hard to tear down.