A decision by the U.S. Department of Agriculture to cut the number of food safety inspectors at a Petaluma slaughterhouse is coming under new scrutiny this week, with federal prosecutors alleging that Rancho Feeding Corp. employees processed 180 diseased or condemned cattle after the USDA reduced its presence at the facility.

The USDA transferred one of its inspectors assigned to the plant in October 2012 and did not replace the individual, said Paul Carney, a regional president for the union that represents USDA inspectors.

“Looks like it started right after, didn’t it?” Carney said of the alleged criminal activity.

A federal indictment unsealed Monday alleged that Rancho’s owners and two employees illegally processed 180 diseased or condemned cattle between January 2013 and January 2014. While no USDA employees were charged in the alleged scheme, several members of Congress are demanding the agency explain how such crimes could have taken place at a federally inspected slaughterhouse.

“They clearly dropped the ball,” said Rep. Jared Huffman, D-San Rafael.

Huffman, who has criticized the USDA as “extremely secretive,” said the number of inspection staff on hand is just one of the many questions facing the agency about Rancho. Just as important is how well the staff members were doing their jobs, he said.

“Clearly there’s at least one more shoe that needs to drop,” he said.

The USDA again declined comment this week, citing the criminal case as the reason for the agency’s silence.

Prosecutors this week charged Rancho co-owner Jesse “Babe” Amaral Jr., and employees Felix Cabrera and Eugene Corda with circumventing inspection procedures and processing impure meat in violation of federal law. The three also are charged with mail fraud conspiracy for allegedly billing ranchers to dispose of their condemned animals even though the cattle actually were processed for food.

Rancho co-owner Robert Singleton is cooperating with prosecutors and expected to plead guilty to a single count of distribution of adulterated meat, according to court records.

The eight-month investigation at the former Rancho plant on Petaluma Boulevard North triggered a recall of 8.7 million pounds of beef and veal sold in the United States and Canada — all that was processed there in 2013. Rancho closed in February and the plant was sold and reopened in April by Marin Sun Farms.

The indictment unsealed Monday said the fraudulent processing of condemned cattle and those with cancerous eyes began “in approximately mid to late 2012.” More specifically, it alleged that Rancho had processed approximately 101 condemned cattle and 79 cows with eye cancer between January 2013 and January 2014 — after the union says the agency had reduced the number of inspectors at the plant.

“The high jinks seem to have happened when that position was eliminated from Rancho,” said Tony Corbo, a senior lobbyist with Food & Water Watch, a consumer advocacy group in Washington, D.C.

The USDA has yet to say how many inspectors worked during a normal shift at Rancho. Carney, a council president on the National Joint Council of Inspection Locals, said he believed the facility typically had one inspector per shift after the October 2012 reduction in staff. Bill Niman, a Marin County cattle rancher, said he and his staff typically saw two inspectors on hand, one of whom was inside watching the production line as the dead animals were processed. Their work was supervised by a USDA veterinarian assigned to the plant.

Corbo acknowledged that more inspectors wouldn’t necessarily stop all criminal activity at a plant. But the relocated inspector had been specifically tasked with monitoring the treatment and behavior of older cows in the facility’s outdoor pens, Corbo said. Since prosecutors allege that Rancho was intentionally buying at a discount cattle with signs of eye cancer, that inspector might have been able to monitor a pattern of questionable behavior, he said.

“That particular facility was ripe for problems to develop in terms of diseased animals presented for slaughter,” Corbo said.

To ensure food safety, Rep. Mike Thompson said the federal government has to do everything it can to thwart “bad people willing to do bad things to make a buck.”

“In this case, it sounds like extra eyes would have helped,” the St. Helena Democrat said.

Thompson said he also will join in the efforts to learn what happened at Rancho and what can be done to improve the inspection system.

“I think we have a lot of work to do,” he said.

Some critics noted that the lack of inspectors still doesn’t explain how the USDA failed to track 101 condemned cattle whose carcasses were supposed to have gone to a rendering plant, nor does it clear up how 79 cows with eye cancer were able to get through the system — even if Rancho employees managed during lunch breaks to cut off their heads and substitute the heads from healthy cows for inspection, as prosecutors allege.

Such concerns prompted Huffman to say this week that the plant’s USDA supervising veterinarian was “either so negligent or complicit” in the activity at Rancho that the man reportedly retired when the recall was announced.

Huffman recalled that last winter Agriculture Secretary Tom Vilsack emphatically denied to him that there had been a breakdown in the inspection process at Rancho. However, Huffman said, “at this point, I just don’t buy that.”

A spokesman for Rep. Robert Aderholt, R-Ala., chairman of the House Agriculture Appropriations Subcommittee, said Congress has provided the agency’s Food Safety and Inspection Service with all the money requested for the past three years, a period when he said many other agencies faced considerable budget cuts. In return, regulators are expected to use those resources properly “to mitigate risk.”

“Obviously they fell short in this instance,” spokesman Brian Rell said.

The USDA’s Office of Inspector General is expected to eventually provide Congress with a report on the actions of both Rancho’s workers and the federal veterinarian and inspectors.

“Chairman Aderholt looks forward to the results of the investigation and to discussing this with the USDA,” Rell said.

You can reach Staff Writer Robert Digitale at 521-5285 or robert.digitale@pressdemocrat.com. On Twitter @rdigit.