Some of the bills, reportedly authored with help from GM, appear to bar startups from testing autonomous vehicles on public roads.

General Motors has denied using political influence and campaign donations to push autonomous-vehicle legislation that has been criticized as anticompetitive.Similar bills under consideration in several states include language that would only allow established automakers to obtain permits necessary to test autonomous vehicles on public roads.

The bills have prompted pushback from Silicon Valley companies that intend to play a significant role in the autonomous vehicle industry, such as Google's Waymo and Uber.

Some companies investing in self-driving systems recently argued the "anti-competitive bill will only slow down the rollout of life-saving technology and create an unlevel playing field at the expense of consumer safety."

An AP report details a lobbying effort and campaign donations from GM to state legislators involved in pushing the bills. In Illinois, the company is said to have donated a combined $8,000 to bill co-sponsors. One recipient of GM cash, state Rep. Mike Zalewski, told the AP he sponsored the bill after being contacted by GM.

"These bills aren't being introduced at GM's urging," said GM lobbyist Harry Lightsey.

GM argues that restrictions on which companies can operate autonomous vehicles on public roads are necessary to avoid accidents that could negatively affect "public acceptance of the technology."

Under pressure from Silicon Valley, some states have changed the language in the bills or declined to introduce the bills altogether. Some critics argue that states should wait for the federal government to manage legislation for autonomous vehicles.