"As Democrats make raising the minimum wage a centerpiece of their 2018 campaigns, and Republicans call for states to handle the issue, both are missing an important problem: Wage laws are poorly enforced, with workers often unable to recover back pay even after the government rules in their favor.

"That’s the conclusion of a nine-month investigation by POLITICO, which found that workers are so lightly protected that six states have no investigators to handle minimum-wage violations, while 26 additional states have fewer than 10 investigators. Given the widespread nature of wage theft and the dearth of resources to combat it, most cases go unreported. Thus, an estimated $15 billion in desperately needed income for workers with lowest wages goes instead into the pockets of shady bosses.

"But even those workers who are able to brave the system and win — to get states to order their bosses to pay them what they’re owed -- confront a further barrier: Fully 41 percent of the wages that employers are ordered to pay back to their workers aren’t recovered, according to a POLITICO survey of 15 states.

"That’s partly because, in addition to lacking resources, states lack the tools to go after the landscaping firms, restaurants, cleaning companies and other employers that shed one corporate skin for another, changing names while essentially continuing the same businesses — often to evade orders to pay back their workers."