Raul Botifoll

Staffing companies and temporary agencies do not automatically perform background checks, said Raul Botifoll, the manager of ManPower Miami, a competing staffing service.

"It's dictated by the client," he said.

While about 70 percent of ManPower's retail customers don't require background checks, large corporations and government agencies often require intensive criminal checks and drug screening, he said.

"But it also depends on the urgency of some of these assignments," he said.

"Employers are significantly more optimistic about hiring than they were a year ago, when 18 percent of companies surveyed thought employment increases were likely and 28 percent intended to cut back," Manpower spokesman Raul Botifoll pointed out.