Guillermo Robles took on two major pizza companies, claiming in lawsuits that the chains discriminated against him and others who are blind or visually impaired and cannot order pizza from a website or mobile app.

Robles, his attorneys and advocates for the blind cite such barriers as a violation of the Americans With Disabilities Act, which requires businesses to accommodate people with disabilities in “places of accommodation.”

Uncertainty over the scope of ADA protections has only increased in recent years, sparking a wave of lawsuits that seek to push the reach of the law beyond entrance ramps and bathroom access for people with disabilities.

“It's not really active, malicious discrimination. It's more discrimination in the form of ignoring their needs and not including them in what's going on,” said Joe Manning, a lawyer in Newport Beach, California, who represents Robles against the pizza chains, as well as several other clients who are fighting in similar cases for website accessibility. “The internet is revolutionizing everything we do. It's everywhere, yet visually-impaired individuals that use the internet via a screen reader don't have access because websites aren't set up.”

Robles is the plaintiff in cases, both in California federal court, against Domino's Pizza LLC and another nearly identical suit against Pizza Hut, owned by Yum! Brands Inc. Recent decisions on these cases and another, in Florida, against grocery chain Winn-Dixie Stores Inc. exemplify the discordant approach courts have taken to resolve questions about access for the blind to websites.

More: How a Miami Ruling Could Affect ADA Compliance Nationwide

The recent cases against Domino's and Winn-Dixie resulted in opposing rulings, and both will head to respective appeals court in California and Florida. In the Pizza Hut case, U.S. District Judge Otis D. Wright II issued a stay and permitted the U.S. Justice Department to intervene and provide clarity about the scope of the ADA. The request was the first time a judge took such action.

The federal government's approach to the ADA is key to understanding the confusion over the ADA.

Since 1996, the Justice Department has said the ADA applies to the Web, but there have not been specific rules in place. In 2010, under the Obama administration, there was a notice of proposed rulemaking to determine the existing obligation for websites to have stricter rules, but no rules were issued.

In July, the Justice Department under U.S. Attorney General Jeff Sessions formally moved “website regulation” to the inactive list of issues that it plans to pursue in the near and long-term.

There is also a split among federal appeals court decisions over whether a business that does not have a brick and mortar location can be considered a place of public accommodation, covered by the ADA.

The judge's ruling in the Pizza Hut lawsuit pointed to the lack of certainty in this area, as well.

Robles's lawsuits against Pizza Hut and Domino's urge the judges to force the chains to change policies and practices to make the website and mobile apps accessible. The companies, meanwhile, argue that unclear standards may still make them liable to lawsuits, even if they invest in new systems to accommodate blind visitors to their websites. A team from Sheppard Mullin Richter & Hampton represents Domino's and Pizza Hut.

In a world that relies heavily on the internet, visually-impaired people have the ability to access websites and mobile apps using keyboards with screen access software that vocalizes the information or displays the content on a Braille display.

“For such screen-reading software to function, the information on a website or on a mobile application must be capable of being rendered into text. If the website or mobile app content is not capable of being rendered into text, the blind or visually-impaired user is unable to access the same content available to sighted users,” according to the complaint against Domino's.

Successful legal actions have been taken against companies such as Apple, Target and Amazon. Certain protocols have been put in place to make it easy for developers to incorporate accessibility features.

There is a universally used system, the Web Content Accessibility Guidelines, to make websites available to blind and visually-impaired people. A case against Apple in 2008 resulted in a settlement between advocates and the Massachusetts Attorney General, requiring iTunes to be accessible to people who are blind. Following this case, Apple developed guidelines for developers to incorporate practices as well.

Many businesses argue that—unlike for websites—there are specific compliance measures they know they need to take with requirements under the ADA. Internet-specific guidelines have not been laid out, and investments made in new technology could still result in more lawsuits. Companies generally say they want to wait for specific guidelines from the federal government before addressing how far the ADA reaches to the Web.

'Serial Litigation' Concerns

The Justice Department has said a business must have an accessible website, but the government hasn't informed parties what that means, said Brad Leimkuhler at Sheppard Mullin Richter & Hampton in California, who is representing Domino's and Pizza Hut. The firm has more than 50 similar cases open around the country, he said.

“Imagine someone says, 'Hey, to keep your restaurant open, you have to make it accessible. Great, how do you do that?' Then you invest money and time into constructing building without knowing what accessible means,” Leimkuhler said. “They do not know the minimal accessibility standard. What's the standard that strikes the right balance?”

Leimkuhler said, from a liability perspective, guessing what standards to apply will continue “serial litigation.”

“It's an issue when you have judges go different ways when you are designing for a different level of accessibility,” he said. “You don't want to be subject to conflicting decisions.”

Winn-Dixie was sued on similar grounds to the cases against the pizza chains in the U.S. District Court for the Southern District of Florida. The grocery chain has appealed the Miami court ruling that said the supermarket chain violated the ADA by not making its website usable via screen reader software.

“We are working in a technologically diverse society and these businesses need to understand that,” said Scott Dinin, the Miami-based attorney who filed the suit against Winn-Dixie. “The ADA does not stop at the storefront.”

Susan Warner, of counsel in Nelson Mullins Riley & Scarborough's office in Jacksonville, Florida, who represented Winn Dixie, declined to comment.

More: 'Winn-Dixie' Ruling Stresses Importance of Website Accessibility

Dinin said there is enough ambiguity in leadership surrounding this issue that allowed certain businesses to take a contrary view.

Manning said there is an unusual situation with Pizza Hut because a UK-version of the brand's website accessibility has features that allow visually-impaired users to access it.

“We've gotten a lot of pushback that we don't know what the standard is, but what don't know how to make it accessible,” Manning said. “But, you can't buy pizza. That would be the first thing to ask, 'Can they buy pizza?' A visually impaired person or screen reader can't buy pizza. They are excluded.”

Angelo Amador, executive director of Restaurant Law Center, which plans to file friend-of-the-court briefs in the Winn Dixie and Domino's cases, said he hopes for clarity over accessibility to tamp down on “drive-by lawsuits.”

“I want clarity and we have a strong argument that do not. Businesses are trying to make websites accessible but it's not easy,” Amador said. “There is some technology there but what do you mandate when technology is moving so fast.”