"Each year, state lawmakers across the U.S. introduce thousands of bills dreamed up and written by corporations, industry groups and think tanks. Disguised as the work of lawmakers, these so-called 'model' bills get copied in one state Capitol after another, quietly advancing the agenda of the people who write them."

So begins an important story out today and prompting crucial questions about the limitations of open government and the state of public ethics in statehouses nationwide. It's the result of two years of collaboration among USA Today, the Arizona Republic and the Center for Public Integrity.

For special interests, writing so-called model legislation and offering it to friendly legislators to introduce as their own can be a highly effective means of conducting an advocacy campaign with minimal cost and even less public exposure. To good government advocates, it's a sneaky way to subvert campaign finance and lobbying disclosure rules.

"This work proves what many people have suspected, which is just how much of the democratic process has been outsourced to special interests," said Lisa Graves, co-director of Documented, which probes corporate manipulation of public policy. "It is both astonishing and disappointing to see how widespread ... it is. Good lord, it's an amazing thing to see."

The newspapers' reporting turned up more than 10,000 bills introduced in state legislatures in the past eight years that were almost entirely copied from model legislation written by advocates; more than 2,100 of them became law. The CPI, a non-profit investigative news operation, conducted a separate analysis that found thousands of bills with identical phrases and then traced the origins of the legislative language back to outside groups.

Most of the copycat measures pushed causes of businesses and social conservatives in many states at once – making it tougher for injured consumers to file liability lawsuits, for poor people to get food stamps, for cities to restrict short-term rentals, for nursing home patients to press complaints and for women to obtain abortions, for example. But others were pushed by progressives, including curbs on protests from the right and new taxes on sugary drinks.

Several of the most successful copycat campaigns were the work of the American Legislative Exchange Council, or ALEC, which specializes in bills to deregulate industries and limit litigation. Its model Asbestos Transparency Act, which aims to make it harder for people damaged by the cancer-causing chemical to win damages, has been introduced in at least 32 states since 2012 and has become law in a dozen of them.

Former House Speaker Newt Gingrich has called ALEC "the most effective organization" at spreading conservatism and federalism in the statehouses.

But not all the copycat bills were promulgated by moneyed interests. One successful campaign the reporters found boosted the strength of several states' sex offender registries and another made it easier for members of the military to vote.