The house of cards built by Congress that developed into the $19.4-billion-a-year tribal casino industry has been wobbling in the nation's political wind for years and is now closer than ever to toppling.

Legal loopholes and regulatory shortcomings have long been evident in the 1988 Indian Gaming Regulatory Act that empowered the nation's mostly impoverished tribes to offer legalized gambling on their reservation lands.

The act was a hasty response by Congress to a 1987 Supreme Court ruling that flung open the door to tribal gambling.

The act, however, is an unfortunate hash of compromises that divvied up regulatory authority among tribes, the states and several agencies of the federal government.

Dispute resolution was left mostly in the hands of the federal courts where tribes, the states and the feds have been arguing about the fine print ever since.

Criticism of the act has been building to a critical mass for years and many in Congress are itching to rewrite the thing and get it right.

Meanwhile, other thunderclouds are gathering.

Arizona Sen. John McCain, chairman of the Senate Indian Affairs Committee, has made no secret of his distaste for "reservation shopping" by tribal casino operators seeking to migrate off reservation to more lucrative urban markets.

Iowa Sen. Charles Grassley, chairman of the Senate Finance Committee, is examining questionable fiscal practices by charitable and other tax-exempt organizations. One issue to emerge is tribal use of tax-exempt bonds to finance casino construction.

A startling decision by District of Columbia federal court Judge John D. Bates might be the final straw that forces a congressional rewrite of the act.

Bates recently ruled that the National Indian Gaming Commission, which administers the federal act, does not and never had legal authority to regulate full-scale tribal casino parlors.

The judge said that role was reserved by Congress for the states in partnership with the tribes.

That was news to the federal commission which has been regulating tribal casinos for the better part of two decades now.

The commission fired off a terse public statement that it would continue to perform its regulatory chores as long as legally possible.

"The NIGC disagrees with the decision," it said.

"Until the Commission revises its regulations or a court of competent jurisdiction orders changes in the scope of its ?regulations, it will continue to conduct business as usual."

That's a relief.

Kansas and most of the nation's 26 other tribal gambling host states made their deals with tribes based on the fair assumption the federal commission would play the pivotal regulatory role.

If Bates' decision stands the federal commission would be shoved to the regulatory sidelines - alongside Kansas and similarly passive host states.

By default, tribal gambling commissions would find themselves in the catbird seat regulating the very casinos they own, and with only spotty state and federal oversight.

It is arguable that that has been the case in many states all along.

A similar conflict of interest helped to bury legislation pushed earlier this year by Kansas Gov. Kathleen Sebelius that aimed to establish state-owned casinos regulated by the state.

However, the nation's 367 tribal casinos are very much open for business - and now under a legally questionable regulatory structure that should send chills up the spines of every gambler.

It is way past time that Congress cleaned up this mess it made.