ALBUQUERQUE, N.M. (AP) – After months of review, New Mexico’s top prosecutor is following through with a lawsuit against one of the nation’s largest nursing home chains over claims of inadequate care.

The state initially sued in December, alleging that the business’ thin staffing made it impossible to provide good care. The suit targeted several nursing homes run by Preferred Care Partners Management Group, a privately held company with operations in at least 10 states: Nevada, Arizona, Colorado, Florida, Iowa, Kansas, Oklahoma, Louisiana, Mississippi and Texas.

The lawsuit used a novel approach to outline its claims, relying on the number of hours it takes to complete basic tasks, from helping residents to the bathroom to feeding and bathing them. With too few nursing assistants, New Mexico alleged residents were not getting the care they needed and the state and federal government were being improperly billed.

Preferred Care Management Partners has argued that New Mexico is targeting practices at facilities that occurred before the company bought them.

The case was highlighted in a New York Times story that detailed the practice of private law firms seeking contracts with state attorneys general to sue companies in the hopes of sharing any money won by the states.

One of those private firms in 2012 approached then-New Mexico Attorney General Gary King to take on the case. The current attorney general, Hector Balderas, initiated a lengthy review after taking over in January.

He told The Associated Press in an interview that it was important for his office to review the merits of the case to ensure it was in the best interest of New Mexicans.

After hearing numerous accounts from residents’ families and former nursing home employees, Balderas said he felt compelled to act.

“We’re dealing with trying to bring about reforms for one of the most abused and neglected populations in our society as well as systemic accountability in what is already a very abused taxpayer health care system,” he said.

Balderas’ office filed a revised complaint late Wednesday that included the stories of more nursing home residents and former employees.

An attorney for Preferred Care said Thursday that the company was reviewing the new claims.

Among the accusations, nurses frequently found residents in soiled diapers and beds soaked with urine because the previous shifts couldn’t complete their rounds. Residents were left on toilets or bed pans for long periods of time, and one facility had several falls a day because residents’ calls for help went unanswered.

In one case, a resident’s care plan called for him to be fed pureed food. He choked to death after eating a hamburger with no supervision, according to the lawsuit.

“These tell-tale signs confirm that the defendants did not provide the basic care that was required and paid for and highlight the very human toll of understaffing,” the lawsuit states. “Defendants’ staffing practices saved them the cost of labor, but cost residents their dignity and comfort and jeopardized their safety.”

The complaint states that since 2008, the nursing homes generated more than $236 million in revenue. The state and federal government paid for nearly 80 percent of that care through Medicaid and Medicare.

To get that money, the nursing homes promised to comply with federal and state regulations.

New Mexico’s lawsuit relies on an industrial simulation of how long it takes to complete basic care tasks. By calculating the total minutes required to properly care for residents and comparing them with the actual number of hours worked, the state found deficiencies of as much as 50 percent in the total hours worked by nursing assistants.

If the state were to win its case, Balderas said he’s optimistic about nursing home reforms.

“The first step in change is holding those accountable,” he said, “and I think this litigation will bring out not only the failures, but I’m optimistic it will identify solutions.”

(Copyright 2015 The Associated Press. All rights reserved.)