On Monday, California lawmakers are preparing to announce a deal, according to the state's newspapers, to raise the minimum wage statewide to $15 an hour by 2022, becoming the first state to meet a target that over the past few years has gone from a pie-in-the-sky activist demand to the new baseline for big cities.

The agreement comes as a labor-backed initiative that could also have raised hourly wages qualified for the 2016 ballot. And it follows the lead of Los Angeles and San Francisco, which already had passed $15 minimum wages. Similar dynamics are at play in New York; Washington, D.C.; Washington state; and Oregon.

According to a quick analysis by the Berkeley Institute for Research on Labor and Employment, the plan would raise the wages of more than 5 million low-paid Californians — about 38 percent of the workforce — by an average of $4,000 annually, paid for by what the group called “modest” price increases on consumers.

"These large and widespread pay raises will substantially reverse the past three decades of growing wage inequality among California's low-paid workers,” said the institute’s Michael Reich.

In most states in the U.S., however, the story is very different.

Instead of raising the floor for wages and working conditions, a growing number of states have been creating ceilings — preventing increasingly active cities and towns from going above the state-level maximum. That’s happened a number of times with the minimum wage, most notably in Alabama, which in February passed a measure to block Birmingham’s attempt at raising its minimum wage to $10.10 an hour, over the state minimum of $7.25.

The tactic is similar to one being used in several states to “pre-empt" their localities from enacting stricter gun laws, and it’s being employed for other kinds of measures, too. Arizona’s legislature is in a war with its cities over whether they have the right to mandate that employers offer paid sick leave to their workers; the state Senate passed a bill denying state funds to any locality that does so. North Carolina just passed a law barring cities from passing their own ordinances against discrimination on the basis of sexual orientation.

Perhaps the most thorough example of pre-emption comes in Tennessee, which a few weeks ago finalized a law preventing localities from enforcing ordinances that require a certain number of local residents to be hired on public construction projects. Such requirements are common in cities across the country that wish to provide jobs for people in the neighborhoods most affected by new developments, and in 2015, Nashville’s voters had approved a measure setting a standard of 40 percent local hires on public contracts.

"It’s certainly among the most extreme in terms of the range of local measures that the state is willing to prohibit,” said Ben Beach, legal director of the Partnership for Working Families, a network of progressive groups that have frequently been stymied by state preemption laws. "Tennessee now has the dubious distinction of being the only state to outlaw cities when they want to spend their own money."

Having done that, the legislature is now looking to torpedo another idea on which discussions had just started in Nashville: an “inclusionary zoning” ordinance that would require a percentage of new apartment buildings to be priced at below market rates, also common in urban areas where rents are rising quickly. Legislators backing the pre-emption measures say that allowing cities to pass their own standards is bad for business, and that the free market is a better way to create jobs and affordable housing.

But the free market hasn’t worked so well for low-income residents in many urban areas, say groups pushing for measures.

"All of these provisions, whether it’s local hire or inclusionary zoning, are all efforts designed to attack the issue of systemic poverty,” said Jason Freeman, an organizer with Nashville Organized for Action and Hope, a coalition of churches and community groups. "And slowly but surely, the state is taking away all the tools that we have to address the problem.”

State legislators who push laws preventing cities and towns from acting on their own often cite a desire to avoid a “patchwork” of regulations that businesses would find difficult to navigate. If lawmakers want to raise standards, the logic goes, they should do so on a statewide basis.

Having uniform labor laws, for example, would prevent businesses from fleeing one jurisdiction for another simply to avoid higher costs. The problem is, states like Alabama that smack down cities’ ability to raise their own minimum wages tend not to have the conversation about doing so statewide at all.

And if the trend continues, the divide between states like California that set floors for cities to rise above and those like Tennessee that set ceilings that everyone must stay below will continue to grow.