RALEIGH — North Carolina’s treasurer is proposing reducing the power of her office by replacing her sole authority for deciding how to invest the state’s $87 billion pension fund with a panel of experts.

North Carolina’s pension fund is one of the country’s strongest and has assets enough to cover nearly all retirement promises to nearly 900,000 public employees and retirees. That strong position has helped make North Carolina one of a handful of states with the top credit rating from all three major rating agencies, saving all taxpayers money on borrowing costs. Good investing has avoided big infusions of taxpayer money to meet pension promises.

But Treasurer Janet Cowell said all that could be imperiled by a successor’s bad decisions or decisions to steer money toward favored financial firms that don’t deliver the targeted 7.25 percent annual returns.

“If you had someone with nefarious intent, you could start firing staff with integrity, start bringing in people that were friendly to you,” Cowell said. “It would be possible to unravel the checks and balances that we have in place in the office.”

So Cowell said she’s willing — under the right circumstances — to give up the solo control of state pension investments in effect only in North Carolina, New York State, Connecticut, and Michigan to a board of trustees.

A panel picked by Cowell split 7-4 last month on whether pension investments should be decided by an appointed commission or remain with the treasurer. The panel’s majority favored replacing the treasurer’s solo decision-making, but the panel’s four legislators divided, with Democrats and Republicans on each side of the issue.

But many legislators like the fact that the current system makes it clear the state treasurer gets the credit or the blame for how pension investments perform.

“People elect the treasurer to make these kinds of decisions,” said Senate leader Phil Berger, R-Rockingham. “The treasurer has the ability and the authority to seek advice and to set up whatever kind of advisory group that she sees fit to help her with that. But I think ultimately the buck has got to stop somewhere and I think the people expect that to be the treasurer.”

The debate with state legislators likely will have to wait until next year, when lawmakers spend six months or more on the job in Raleigh, Cowell said. The General Assembly started this year’s shorter session on May 14.

Cowell says an investment commission should have the flexibility to decide how much to invest in stocks, bonds or other asset classes. Lawmakers also should increase the number of investment professionals on the state’s payroll, she said. The two dozen investment advisers on staff now is about three times fewer than similarly sized large pension funds, Cowell’s office said.

“It’s not a sexy headline because it’s not a simple answer. It really does depend on the details,” Cowell said. “If we have the right combination, a board could be a better way to go.”

The union representing about 55,000 state employees isn’t impressed by Cowell’s talk of trading away her massive authority. Replacing the treasurer’s sole authority over pension investments with a commission is something the State Employees Association of North Carolina has been demanding for years.

“Politicians often say they’re open to doing something later. What should matter to you is what is a politician willing to do now,” SEANC chief lobbyist Ardis Watkins said.

Cowell established a series of ethics and investments rules since taking office in 2009. Yet too much is still hidden behind a veil of finance industry secrecy, Watkins said.

“Anybody interested in our pension fund should demand to see exactly what’s going on with our dealings with them,” Watkins said. “We should put blind faith in no one.”

North Carolina’s pension funds saw a 2.2 percent return in the first three months of this year and 11 percent in the previous 12 months, a quarterly report by Cowell’s office said Thursday. The pension fund’s value has grown by more than 45 percent since in 2009, when stocks were being beaten down in the midst of the Great Recession.