The Massachusetts CORI law was passed in 1972 to restrict dissemination of criminal histories to law enforcement agencies but evolved into a central registry to check the backgrounds of employees and volunteers at health care facilities, schools, and other organizations that deal with vulnerable populations.

Under the latest CORI overhaul, all employers, landlords, and background screening companies can access the Internet-based registry. But these checks will reveal no more than 10 years of criminal history, with the exception of homicides and sex offenses. They also will not include old arrests that did not result in a conviction.

The rationale for the limit, according to the state, is to provide greater opportunities for offenders who stay out of trouble to reintegrate into society.

Jenna Knight, 40, a recovering crack cocaine addict and alcoholic, racked up several felonies, such as writing bad checks and breaking and entering, two decades ago. She has been sober for 17 years and earned a bachelor’s degree in 2005, she said, but has not been able to land a job because background checks turn up her old offenses. As a result, she gets by largely on Social Security disability payments.

“I wanted to be self-sufficient,’’ said Knight, who lives in Worcester. “I didn’t want to live off the state all my life.’’

More than 90 percent of companies conduct criminal background checks on at least some job candidates, according to a 2010 survey by the Society for Human Resource Management, a professional association in Alexandria, Va.

Donald Washington, a case manager at a Worcester social services agency, said such checks kept him from getting jobs for years after he completed a prison sentence for stealing from his employer in the early 1990s - though he never faced another criminal charge.