The Securities and Exchange Commission last week disavowed part of a joint government study of last year's silver market crisis and challenged the Commodity Futures Trading Commission's evaluation of a crucial question about the cause of "Silver Thursday."

THE SEC delivered its objections to a congressional committee within hours after the study itself went to Capitol Hill.

The action brought into the open a long-smouldering dispute between the SEC and CFTC over what went wrong in the silver market and what should be done about it.

The two agencies were ordered by Congress to collaborate -- along with the Treasury and Federal Reserve Board -- on the joint study, but both are conducting their own investigations of possible violations of law.

THE CFTC did most of the work on the critical sections of the joint study that deal with the rise and fall of silver prices, the SEC said, "and we have made no independent verification or analysis of this information."

The SEC's own investigation is still underway and "may not support and in fact may be inconsistent with" what the CFTC said, the securities agency told Sen. Richard Lugar (R-Ind.) chairman of an agriculture subcommittee.

The SEC specifically objected to the CFTC's evaluation of the impact on silver prices of changes in the rules of the two big silver markets, the Commodity Exchange Inc. in New York and the Chicago Board of Trade.

The billionaire Hunts of Texas, who lost more than $1 billion when silver prices plunged from $50 an ounce to $10.80, have repeatedly blamed the exhanges for their loss.

The report says the rules changes "appeared to contribute to reversing the upward price movement." The SEC disagreed saying, "We believe that the exchanges' actions may have been a significant factor in the decline in the silver markets," and calling for further study of the issue.