BOISE - Relatives who accompany Idaho government officials on business trips to New York City should repay the state if their presence adds to ground transportation cost, Treasurer Ron Crane said Tuesday.

Last week, The Associated Press reported records it obtained showed Crane's office spent nearly $10,000 since 2009 on stretch limousines and executive sedans to transport state employees and their families while in New York as part of meetings with ratings agencies to discuss Idaho's credit-worthiness. Taxis, in some instances, would have been cheaper.

In an interview Tuesday at his Capitol office, Crane said transporting officials by limousine in Manhattan to meetings with Standard and Poor's and Moody's Investors Services remains an effective use of taxpayer money. It allows them to travel together without risk of getting split up, he said.

But Crane noted instances where relatives added to costs, including for extra cars carrying their luggage from the airport to their hotel near Central Park, were inappropriate. If spouses or children increase the bill, they should pay for it, he said.

"If we're forcing additional car usage because of spouse attendance, that needs to be something we address as far as reimbursement," Crane said. "But if it happened in the past, it was an oversight."

Crane also plans to put a stop to officials riding alone in a stretch limousine, which happened on several occasions.

A limousine from New York's John F. Kennedy International Airport to Manhattan cost Idaho about $250, according to state records obtained by the AP. Meanwhile, a taxi from JFK to Manhattan costs about $50, according to the New York City Taxi & Limousine Commission.

Idaho's Legislative Services audits division is conducting a review of Crane's office management for the past three years, including transportation expenses in New York City. Audits division manager Don Berg has said the review is unfinished and he won't comment until it's released.

The treasurer's trips every June are popular. In 2009, for example, at least six family members including Crane's wife accompanied the eight official members of the delegation.

Family members cover their own flights, meals and Broadway shows, but they haven't generally reimbursed Idaho for ground transportation - even when their numbers necessitated more vehicles. In 2010, two vehicles loaded with only suitcases cost more than $500.

Crane, in his fourth term, said this debate over stretch limousines distracts from important work Idaho officials do in New York helping secure for Idaho the best bond rating possible.

Earlier this year, Standard and Poor's upgraded Idaho's rating, and Crane believes information provided by Idaho officials including economists, legislators, private financial advisers and underwriters during the New York trips played a role. Investment grade ratings reduce interest costs not only for state government but for Idaho school districts and other units of local governments, he said.

Crane said Idaho has injected $20 million in interest revenue into the state general fund over the last decade, because its stellar rating allows it to reap about $500 million annually from short-term debt securities sales at interest rates of less than 1 percent.

It then reinvests the proceeds at higher interest rates until the money is needed.

"I have tried repeatedly to get reporters to come in and talk about the (NYC) trip and the value that it has to this state and the $20 million we have made that have gone to the general fund over the last 10 years," Crane said. "What they're interested in is, 'What hotel did you stay in? Where did you have dinner at? How did you get from point A to point B?' That is a frustration to me, as a public official. ... And the other thing that I would point out to you, I haven't done anything different from my predecessors."

Crane, a former state lawmaker from Nampa, did say he's reduced the trips' costs since taking office in 1999.

Idaho's entourage now stays in a "centrally located hotel," The London NYC, allowing its members to walk to restaurants rather than hiring an extra car. And the trips have been trimmed to five days, down from six, he said.