TUCSON (KGUN9-TV) - Police say Michael Ray Hill went some dark places on the internet.
They accuse him of uploading more than 200 pictures of boys perhaps as young as six doing things, we will not describe.
He's out of jail on bond now.
Speaking through his screen door, he told us, "I don't have no comment about it. I said my case already to the police."
And police told a judge they heard about Hill from Google, which saw what Hill was doing in the shadowy world of the internet.
Tucson Police Sergeant Chris Widmer says, "Stuff's easier to hide for people on the internet."
Detectives say Hill uses Google Gmail and something about his account set off alarms. So Google told the National Center for Missing and Exploited Children, and the Center told Tucson Police about this new piece of a huge problem.
Michelle Collins with the Center says, "I can tell that in 2012 alone we received more than 415 thousand reports regarding child sexual exploitation online."
And 84 percent came from U.S. providers like Google. So how does Google spot child pornography? They aren't saying, but when they do find it, the law requires them to report it.
It says it right in their privacy statement, "We will share personal information...", especially if Google has a legal reason---like a possible crime-- to share it.
Anything you send through Google. They may track because that's how they know which advertisements to send you.
UA Law Professor Derek Bambauer told us, "A lot of people worry about this because they're just concerned with someone looking through their stuff."
Bambauer is an expert in internet privacy.
About Google, he says, "They're giving you a free service in exchange for them looking through your e-mail looking for keywords."
And if you are breaking the law there are ways they can spot that too.
Bambauer says there's a federal database that actually tracks known pieces of child pornography that circulate on the web. He suspects Google checked Michael Ray Hill's files against that list.
Back at Michael Ray Hill's front door, he said, "You guys don't need to keep broadcasting this all over the television."
But now police worry, there's more to this case---more children police think Michael Ray Hill might have contacted on the internet.
TPD Sgt. Chris Widmer says, "The concern is what else happened between them."
So the investigation continues---an investigation that started with Google.
Experts tell us it is also possible for you to get a computer virus that can take over your computer, and use it, or your email address, as a pipeline for someone else's pornography.
So when police get these cases, that is one of the things they have to figure out.