As online dating has mushroomed into a $1-billion industry over the last decade, the debate over the obligation for dating sites to conduct criminal record checks on its subscribers has become increasingly contentious.

The issue exploded in the United States in March 2011 after a Los Angeles television producer claimed she had been raped by a man she met on Match.com, North America's biggest online dating company.

"If they had done screening, my case would have been preventable," Markin told CBC News.

When she began researching her date — after the rape — Markin was shocked to discover he had previous convictions for sexual battery. She filed an injunction against Match.com, demanding it cease accepting new members until it instituted a criminal screening process.

"In general, when you are paying money for a service, you don't think there will be criminals. I was paying $15-20 a month. I know that people lie about their age, or income, or their looks, and it's hard to check that. But I didn't think they would ever let a criminal on the site because you can check that."

The case was eventually dropped and Texas-based Match.com recently began screening daters against the U.S. National Sex Offender Registry. It told CBC News the decision is not related to Markin's legal action. Meanwhile, Markin's assailant pleaded guilty to assaulting her.

The general reluctance to conduct background and criminal checks is attributable to pragmatic and financial reasons, according to Dave Evans, who publishes the Online Dating Insider and is a consultant to online dating companies.

Online dating companies are often transnational companies, whose customers live in several countries, each with different rules about access to criminal information. With limited or sporadic access to records, liability is a concern.

"People can always slip through the cracks and I think that's the fear of the big dating sites," Evans said.

Dave Evans, a consultant to online dating companies, says they need to make a "best effort at filtering out the bad apples." (Photo sumitted)

In the U.S., court and justice-related records are available to the public and scattered across the country. There is a federal sexual offender registry, along with prison records and court records at the state and county levels. But there are differences among states and how much information they will reveal.

Database companies have sprung up to try to amass these records into corporate databases and sell the information to online dating companies. However, no one corporate database claims to contain the bulk of all known records that would reveal the entire criminal history of an individual. And there is no central, governmental or institutional database that contains this information.

A handful of U.S. states has ordered online dating companies to post notices on their homepage, warning daters that no background or criminal record checks are conducted.

Still, dating sites need to make a "best effort at filtering out the bad apples. That's something that the whole industry has definitely not wanted to touch for the last couple of years," Evans said.

High profits, low expenses

Online dating websites, according to Evans, are interested primarily in low expenses and high earnings, which are achieved by attracting and retaining as many online daters as possible.

"It's really about reducing your customer acquisition cost and keeping people around for as long as possible," Evans said.

Conducting criminal record searches on daters would take a bite out of earnings. In the U.S., corporate verification companies charge up to $20 per background and criminal record check of varying degrees. The price normally drops for bulk orders in the tens of thousands.

Online dating sites refute criticisms that they are cheap or unconcerned about the safety of their clients.

Cary Berger, the general counsel for eHarmony, said his company does not do criminal record checks because it doesn't want to give clients "a false sense of security" by providing a "thumb-up or clearance" on daters.

eHarmony says it does not do criminal record checks of its users because it doesn't want to give clients a false sense of security. (CBC)

"And so, what we do is we actually make it very clear in several places throughout our site that we do not conduct criminal background checks and that it's very important for the members to use some of the safety tips that we provide to them in order to make sure that, you know, they are as safe as they can be in the relationships they form on our site," said Berger.

Free dating sites are not known to do any criminal checks at all. Evans said that's because they're only focused on attracting as many daters as possible, and more "eyeballs to the sites" mean more advertising revenue.

Companies that do some basic form of background checking in the U.S., like Match.com, keep the information quiet, according to Evans, because they don't want to risk losing actual or potential earnings by turning off or scaring away potential daters, who might consider the checks an invasion of privacy.

Going against the grain

There is one online dating company which has instituted criminal background checks into its membership policy. Texas-based True.com charges a monthly subscription, part of which pays for the screening that is required to join its site.

True.com founder Herb Vest says a background search for criminal convictions is a requirement of membership on his site. (Donna McWilliam/Associated Press )

"Internet dating is populated, to a large degree, by criminals and married people," founder Herb Vest told Forbes magazine. "We do a background search for criminal convictions. It covers more than 90 per cent of felony convictions (in the U.S.). I take it personally – you can go anywhere else, but don't come onto my site."

In 2006, he says True.com blocked 25,000 Americans from its site.

Vest told Forbes he was committed to criminal checks because his father was murdered.

"The two are very connected … And my determination to prevent murders, rapes and crime from occurring has become a passion."

True.com uses S2Verify, a company that charges about $20 to conduct a search of 500 million records it has collected from U.S. courthouses, the U.S. Department of Corrections, Bureau of Prisons and county criminal records. The company said True.com considered operating a site in Canada, but decided the cost for the RCMP criminal record check was prohibitive.

David Evans said he has given up trying to convince the industry to invest in at least some type of background checking.

"You could talk yourself until you're blue in the face about this, this whole idea: that if you make it safer and easier for people to find each other, you're going to do better in your business. But with the dating industry, with 1,500 sites … It's the Wild West out there."