COLUMBIA -- South Carolina's chief financial officer said Tuesday he wants further study on a proposal to create an independent investment company that would manage a portion of the state's finances.

The state commission that oversees public employees' retirement system voted last week to proceed with steps that could put South Carolina's private capital investments under management of a state-owned firm.

Treasurer Converse Chellis said then that he agreed with the idea of saving on fees as a way to boost the state's return on investment and reduce the potential cost of retirees' pensions to taxpayers and employees, though he requested more details.

The unfunded liability of the state's retirement plan is $12 billion over 30 years. An 8 percent rate of return, set by lawmakers, would make that up, but that's a daunting task in the economic downturn.

However, a day before the commission's chief investment officer is set to present the plan to the state Budget and Control Board, Chellis said the proposal lacks details and has sowed too much confusion and unease.

"We need many more sets of eyes examining the possible formation of a new company," Chellis said in a statement Tuesday. "A decision of this magnitude cannot be rushed."

As treasurer, Chellis sits on both the commission and budget board.

The state Retirement System Investment Commission voted unanimously last Thursday to commit up to $15 million to what could be the first investment firm of its kind nationally.

State law, which was designed to remove state investing decisions from politics, allows the commission to create the firm without seeking permission from state lawmakers. But its members, who are picked by the Budget and Control Board, agreed to revisit its vote after getting feedback from the board. Chellis said he plans to ask for a delay.

That board also consists of Gov. Mark Sanford, the chairmen of the House and Senate budget-writing committees, and the state's chief accountant.

The plan involves the newly created company investing in private capital, such as real estate and South Carolina companies, which the commission's chief investment officer, Bob Borden, says would help create jobs. About 20 percent of the state's $24 billion retirement trust fund is invested in private capital.

A consultant's report suggests the plan could save the state about $500 million in management fees over the next decade, by cutting in half the initial investment fees and reducing the cut of profits normally taken by private investment managers.

Employees in the South Carolina firm would be paid through those reduced fees.