The attorneys general of most states, including our own, are having a frustrating time of it with internet ads.

Specifically, they're fighting human trafficking that they say may include providing children for adults seeking sex.

Washington Attorney General Rob McKenna is leading the effort, with 45 other attorneys general behind him.

All have signed a letter to Backpage.com, asking the website to prove that it has strict content policies aimed at preventing child sexual exploitation and human trafficking.

The goal is a worthy one -- trying to stamp out child prostitution.

Backpage.com says it has tough policies.

For the state's top prosecutor to ask them to prove it goes beyond what most of us expect.

Proving innocence has not been necessary in this country since adoption of the Constitution. The attorneys general are not, however, demanding anything.

They're asking.

That seems reasonable.

"Traffickers who exploit runaways and other disadvantaged kids shouldn't be provided with a powerful online clearinghouse," said McKenna, a Republican.

"The only way for Backpage.com to completely stop child sex trafficking on its site is to take down adult services advertisements altogether and take aggressive steps to be sure such ads don't surface elsewhere on the site."

A glance at the website leaves no doubt that sex trafficking of the male/female, male/male and female/female types are available through the classified advertising.

But we could find nothing in the classifieds under "escorts" that openly involved children.

Our hurried scan is emblematic of the problems the states are having in trying to protect children.

There are so many ads, often worded more or less alike, that finding out what is really being advertised could take a lot of time.

It's not as though the states don't have reason for concern.

The letter to the company says illegal sex ads (prostitution is a crime in most states) is a magnet for those seeking to exploit minors.

More than 50 cases, in 22 states over three years, involved the trafficking or attempted trafficking of minors through Backpage.com, according to the attorneys general letter.

"These are only the stories that made it into the news; many more instances likely exist," they wrote.

They also reminded Back page.com of a 2010 request from nearly two dozen attorneys general asking that the adult services site be taken down.

Industry analysts suggest that adult services advertisements are worth about $22.7 million in annual revenue to Village Voice, the parent company of Backpage.com.

We'd like to see all online classified advertising companies take great pains to prevent their sites from being used for the sexual exploitation of the young.

In that light, we'd also encourage the owners of Backpage.com to give the attorneys general what they are asking for.

The same for Backpage.com's competitors.

The sexual abuse of children is despicable, and beyond the hurt of the children themselves, it renders irreparable harm to civilization itself.