NEW YORK — Mariner Investment Group, a hedge fund founded by a former Bear Stearns fixed-income executive, charged South Carolina’s pension fund more than any other manager while delivering returns that trailed competitors.

Mariner, started by William Michaelcheck, 65, got $38 million in fees from the South Carolina Retirement Systems in fiscal 2011, or 16 percent of all the compensation paid to the fund’s money managers, which totaled $239 million, according to pension officials.

The performance of Mariner’s investments for South Carolina lagged behind those of managers such as Bridgewater Associates, the world’s biggest hedge fund by assets. Mariner funds returned from 2 percent to 13 percent last year, while Bridgewater’s delivered 17 percent to 24 percent. Bridgewater collected $25 million in fees, or 34 percent less than Mariner, while managing $1.3 billion in assets compared with Mariner’s $930 million.

“We take the risk and we pay the fees, but we don’t get the reward,” said South Carolina Treasurer Curtis Loftis, a Republican who was elected in 2010 with tea party endorsements and owns a pest control company. “I think it’s systemic. I think it’s happening all across the country.”

Public pensions, seeking to boost returns and reduce volatility after a financial crisis decimated global stock markets, have increased assets allocated to alternative investments such as hedge funds and private equity. Fees for those investments are higher than for traditional stock and bond funds, and returns sometimes trail the 8 percent average yearly gains officials set as their benchmark to pay the rising costs of pensions for public employees.

The $26.2 billion South Carolina pension fund, which raised its holdings of alternative assets to about 40 percent of its portfolio in fiscal 2011 from nothing in 2007, is re-evaluating the costs it incurs and demanding a better accounting of expenses, Loftis said.

Mariner’s contracts with the South Carolina pension “have recently been renegotiated to ensure alignments of interest and a fee structure commensurate with the desired risk and return profile of the investments,” Adam Jordan, chief of staff for the state’s investment commission, said in an e-mailed response to questions.

While total fees have tripled in the past three years, South Carolina’s pension returns have sometimes been lower than those for funds of comparable size.

For the three years ending June 30, 2011, South Carolina’s pension returned 3.1 percent, not including fees, compared with about 3.9 percent for public funds with assets greater than $5 billion, according to the Wilshire Trust Universe Comparison Service.

South Carolina’s pension jumped into hedge funds, private equity and other alternative investment strategies under its former chief investment officer, Robert Borden.

Borden said cutting the fund’s allocation to stocks to about 30 percent from about 60 percent made it less risky. On a risk-adjusted basis, South Carolina’s was the best-returning pension fund, he said in a telephone interview.

It’s not fair to judge the pension’s performance based on one snapshot, he said. For the three years ended Dec. 31, 2011, South Carolina’s pension returned 12.1 percent compared with about 10.4 percent for similar public funds, according to Wilshire TUCS.

“When you have periods where the equity market rallies up sharply, anybody who’s got that long exposure experiences good performance,” Borden said. “The portfolio is positioned to be very defensive against equity-market selloffs.”