So what can Congress do to avoid this confusion? To many, the answer is simple: get out of the way.
"You want to give the states maximum flexibility as these things evolve," said Rep. Candice Miller, a Michigan Republican and the cochair of the House Intelligent Transportation Systems Caucus. (Blumenauer is the Democratic cochair.)
Miller has introduced a bill that would allow states to use existing transportation funds from highway-safety and other programs to invest in vehicle-to-infrastructure (V2I) projects.
"What we're trying to do is draft language so it's not so prescriptive and it gives the auto companies and the state DOTs and the engineers room to move," said Miller. "We're telling states that you can use the money to do these kinds of things, and you figure out if you want to or not."
Peters, who last week introduced a companion bill in the Senate with Republican Sen. Roy Blunt of Missouri, said the strategy is meant to make it easier for a state to, say, install sensors in a roadway during standard repairs, but leave open the option to just stick to traditional infrastructure.
An aide on the Transportation and Infrastructure Committee working on the chamber's reauthorization bill said the committee is considering just such an approach. The bill—which is still being written—is expected to include language like Miller's that would free up dollars for new technology, and nudge states to explore it rather than sticking to the status quo.
There are also plans to devote money to research in new technology, possibly creating a grant program similar to the X Prize or DARPA that would allow urban areas to build out model cities for automotive cars.
Sen. James Inhofe of Oklahoma, chairman of the Senate Environment and Public Works Committee, which is drafting the Senate version of the transportation bill, said his committee is trying to strike a similar balance that will promote research.
Michigan, home of the auto industry, is among the most advanced states when it comes to V2V and V2I systems, and the state's transportation head Kirk Steudle said he's eager for a new bill to give him "flexibility" to continue the investments. While his state is eager to get connected roadways, he said he also hears from other states more concerned about just staying afloat amid the tight budgets.
"Of course you've got to get your basic things covered, like paving roads and repairing bridges, but when you have that covered, why not have some money for tech research and deployment?" Steudle said. "Make it eligible to come out of federal funds so whoever wants it can be aware."
There's also a role for regulations to make sure the industry is aligned (standards would ensure that Ford cars and GM cars are literally on the same wavelength). The NHTSA in 2013 proposed regulations on driverless cars, and Transportation Secretary Anthony Foxx said last month that the agency would accelerate the rulemaking schedule to send a proposed rule to the White House by the end of the year. Only a handful of states—including Nevada, California, and Virginia—have laws allowing the testing of driverless cars on the roads.