We'd like to think we know them pretty well, some we'd even trust with our own children. But there are more than a handful of people living in Sioux Falls who you wouldn't want around your kids.
A Sioux Falls mother found that out by logging onto the computer and now she wants other parents to see what she found.
They could be walking down the sidewalk, strolling through a school zone, or playing catch in a city park. They are registered sex offenders.
Not all registered sex offenders are dangerous, but there are some who have preyed on little children.
"Sexual contact with a 9 year old, he's a bad guy, yuck," said Jessie Schmidt.
Jessie Schmidt lives in a nice neighborhood near a private golf course. She's surrounded by beautiful homes, tall trees and peace and quiet. The last thing she ever thought she'd find is a registered sex offender.
"The closest one is just two blocks away," said Schmidt.
How does she know? She found out by logging on to this web site, www.familywatchdog.us.
"Here's my house and you can see there's an offender probably just a few blocks away from me," said Schmidt.
Schmidt was not totally surprised when she discovered a man, who was convicted of possessing child porn, living in her neighborhood.
Schmidt feels checking this web site is one way to keep her kids safe from child predators.
"There are a lot of marks on that map."
The map shows where sex offenders live in the city, their picture, their sex crime, and their age when the crime happened.
There's another registered sex offender one mile away. And with two young children, Schmidt feels it's her duty to warn others who may not know.
She sent out an email with the web site attached to over 100 of her family and friends.
"It was the largest email I've ever sent. The devil that you know is always better than the devil you don't know and you can be aware and be that much more cautious and I think why wouldn't I want to give my friends and parents that I know the opportunity to be every bit of aware as I was," said Schmidt.
Schmidt says it may be over reacting, but if it prevents one sexual assault case, it will have been worth it.
"There are bad people everywhere we just need to be aware of who they are, they have a right to live somewhere, but I have a right to be better informed and make proper choices for my family too," said Schmidt.
According to the web site, South Dakota has the most registed sex offenders per capita than any other state except Alaska.
In July of this year, law enforcement went knocking on the doors of all registered sex offenders living in Minnehaha County, to make sure they're still living where they said they were living.
But even that doesn't account for all of them.
"How many individuals have come to South Dakota from some other jurisdiction, we don't know they're here, I share the mother's concern," said South Dakota Attorney General Larry Long.
Long says in South Dakota, it's estimated six percent of sex offenders don't register. And that worries parents like Schmidt.
"If they do what they're suppose to do and the state does what it's suppose to do and everything will be just fine. I will feel more comfortable with them living in my neighborhood, they're the guys I know, it's the ones I don't know that are more of a concern."
In South Dakota, sex offenders are required to check in four times a year. If one moves from South Dakota and doesn't notify the state, authorities issue an arrest warrant for that individual hoping they'll be picked up in another state.
To look at the web site yourself click here
