A convicted child sex offender should not have a job on school property.

Yet Terrance Sago, who was convicted of sexually assaulting a 9-year-old, was hired by Blk & Wht Valet LLC to help Cubs fans park their cars in school-owned lots near Wrigley Field.

Blk & Wht, a Chicago Public Schools contractor, has since fired Sago and told reporters Tim Novak and Lauren FitzPatrick that he lied on his job application and didn’t disclose his criminal conviction.

EDITORIAL

But surely Blk & Wht figured things out when Sago was arrested on the job back in 2015, for failing to update his address on the state’s sex offender registry. Sago went back to prison for two years — time enough for Blk & Wht to unravel the truth — yet went back to work for the company after he got out of prison.

In fact, Novak and FitzPatrick found Sago on the parking lot of Inter-American Magnet School recently, helping to park cars “with kids swinging on the monkey bars behind him.”

That’s not a picture a parent wants to see.

We strongly believe that businesses should provide job opportunities for ex-offenders, who deserve a second chance after they’ve paid their debt to society. But it’s pretty obvious, we think, that sex offenders should not be hired to work anywhere that could pose a danger to a child.

And in Sago’s case, state law is clear: Convicted child sex offenders are banned from being on school grounds, at any time.

CPS, still reeling from a sex abuse scandal documented in a Chicago Tribune series, is appropriately looking at tightening the rules on background checks for contractors. Blk & Wht has five leases to park cars on school lots, and isn’t the only company with such leases.

Under current CPS rules, those companies are required to do background checks only on employees “who may have contact with CPS students.”

The district now doesn’t think that’s good enough and has asked Maggie Hickey, a former federal prosecutor who’s working with the district in the wake of the sex abuse scandal, to look into “the possibility of requiring renters to background check all personnel, even if they do not have contact with students or work during non-school hours.”

Sounds like a good plan.

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