CHARLOTTE, N.C. – A North Carolina law prohibits registered sex offenders from being on school property but WCNC found out there is a loophole in that law that you may not know about -- until now.

WCNC Defender’s Mark Boyle uncovered how offenders can work around the law and in fact, be given permission to be on campus during special events or meetings.

When you think of a sex offender, you probably think they're not allowed on school campuses. But according to one local school, certain sex offenders are allowed on campus.

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One of these cases was a graduation ceremony at a Cleveland County high school. A convicted sex offender was given permission by the school district to attend a Burns High School graduation ceremony.

Some local parents were so disgusted by it, they reached out to WCNC and now they are demanding answers.

“It makes me nervous, very nervous,” said one parent.

“I think that any sex offender in the county should not be allowed on school property,” said another parent. “Period.”

She said she found out about the sex offender on campus after it had happened.

Instead of doing nothing, she emailed Cleveland County School District Superintendent Stephen Fisher.

WCNC obtained that email communication and confirmed its authenticity.

Fisher wrote the parent a response that reads in part:

In regards to this particular situation, the person in question was given permission to attend graduation. The person was assigned a special parking place and seat. The person was required to check in upon arriving and was monitored while on campus.

We've uncovered a loophole that allows some sex offenders on campus.

Here is Cleveland County School District’s school policy:

A registered sex offender who is the parent or guardian of a student in the district may only be present in school buildings, in school facilities, on school campuses with prior written permission from the Superintendent or designee.

CMS has a similar rule in place that reads:

An individual who is a registered sex offender and is the parent or guardian of a student enrolled in school may be on CMS property only for the following reasons and in accordance with the procedures set forth: to attend a previously scheduled school conference with school personnel to discuss the child's academic or social progress.

Experts say the system is set up to keep sex offenders off-campus but not to monitor them while they're on-campus.

It's a complicated situation, especially during a big event with hundreds of people like a graduation ceremony.

"It becomes all the more difficult to really hone in on whether there's a convicted sex offender there or not,” said Mo Canady of National Association of School Resource Officers.

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As for the case where the sex offender apparently attended graduation, the district says it was just following its policy and wasn't breaking any rules.

As of now, you may never know when a sex offender is on your child's campus. School districts are not required to notify parents when it happens.

And that fact right there doesn't sit well with some.

"We should be forewarned or let somebody knows something," said the parent.

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