The odds for slot machines at casinos in Oklahoma should be regulated and published as a matter of public record just as Nevada does for its casinos.

Today’s Sunday Extra reveals that tribes are not required to maintain or list a particular payout percentage. As the Oklahoma Gaming Compliance Unit informed the Phoenix, “... there are no laws/guidelines, either state or federal that dictate payout percentages (odds) at tribal gaming facilities.”

The Phoenix asked tribes about slot machine odds after receiving a few phone calls from casino patrons who expressed concern that payouts at machines had been altered to lessen the odds of winning.

The gambling experiences of a few people are very subjective. Those experiences are not an adequate measure of whether or not tribal casinos are returning a sizeable portion of what people wager in prize money.

The only reliable measurement can come from the tribes or regulators who reveal the payback percentages or odds. However, the National Indian Gaming Commission and state overseers don’t require it, and most tribes won’t release that information.

The Cherokee Nation told the Phoenix that the nation’s payback percentages are a matter of “proprietary pricing strategy” and they are not disclosed for “competitive reasons.”

Competition in the free market, however, is not fostered by secrecy. Competition is maintained by openness.

We can’t understand why the state, when it negotiated gaming compacts with the tribes, did not include payout percentages as part of the pact. Nevada requires a minimum 75 percent payback of money wagered in slot machines, and Kansas requires each gaming machine to be programmed to pay back 80 percent.

There’s no question that tribal casinos have improved Oklahoma’s economy with new jobs and attracting visitors from out of state who spend their money here. There’s no question that tribal casinos return a healthy portion of their revenues to public projects and services.

But as long as the tribes operate in secrecy, those who play the machines will wonder what kind of odds they’re up against.