WASHINGTON — NASA acted properly when it picked new homes for the retired space shuttles, the space agency’s watchdog said Thursday.

The shuttles were awarded in April to museums in suburban Washington, Los Angeles, Cape Canaveral, Fla., and New York, based on recommendations by a special NA

SA team and a decision by NASA Administrator Charles Bolden, a former shuttle commander.

Congressional and local officials for two of the losing cities — Houston and Dayton — had asked for an investigation, alleging political influences in the bidding process.

“We found no evidence that the team’s recommendation or the administrator’s decision were tainted by political influence of any other improper consideration,” Inspector General Paul Martin wrote in the report released Thursday. “Moreover, we found no attempt by White House officials to direct or influence Bolden’s decision making.”

The decision was based on attendance, population, funding and the facility. NASA said 13 of the bidders met their requirements and rated those on several categories, giving them a numerical score.

There was a scoring error for the Air Force Museum in Dayton and it should have tied with Cape Canaveral and New York, the inspector general found. But NASA chief Bolden told investigators he still would have picked the same cities because they had bigger populations and more international visitors. Also Dayton museum officials told him they might not be able to raise enough money.

Sen. Sherrod Brown, D-Ohio, one of the officials who’d asked for the investigation, said in a statement Thursday that while NASA may have followed the rules in selecting the sites, it showed “incredibly bad judgment.” The selection criteria gave more weight to international visitors than to geographic diversity of shuttle locations, he said.

“It is outrageous that easy access for foreign visitors was deemed more important than access for visitors from America’s heartland,” Brown said.

In a statement Thursday, NASA defended its selections.

“The report from the Office of Inspector General validates the conclusions NASA reached in determining the locations where the space shuttle orbiters will be displayed. NASA firmly stands by its decisions.”

Space Center Houston, next door to Johnson Space Center, ranked near the bottom of the list. It scored low for attendance, international visitors, museum accreditation and difficulty transporting a shuttle there. Museums in Chicago, Seattle, Riverside, Calif., San Diego and McMinnville, Ore., all scored higher than Houston.

Bolden, who lived in Houston for many years as an astronaut and Marine and still has a home there, told investigators that personally, “I would have loved to have placed an Orbiter in Houston,” but that it had lower attendance and fewer international visitors than the winners.

After the report was released, Rep. Kevin Brady, R-Texas, criticized the selection process.

“It’s clear to me this was rigged from the beginning and it was pretty clear Houston would not receive the orbiter,” he said.

The 30-year space shuttle program ended with the last flight in July.

The Smithsonian Air and Space Museum had already been promised one shuttle for its hangar in Dulles, Va. It will get Discovery, and give up the Enterprise, a test vehicle that never flew in orbit. That will be shipped to the Intrepid Sea Air and Space Museum in New York City. Atlantis will stay in Cape Canaveral and go to the Kennedy Space Center Visitor Complex. Endeavour will go to the California Science Center in Los Angeles.

The Florida and California museums, but not the Smithsonian, will have to pay at least $20 million to make the shuttles that flew in space safe for display — removing toxic materials and fuels — and transportation costs. NASA is picking up the tab for the Smithsonian. The shuttles are all still at Kennedy Space Center being decommissioned.

Associated Press Lisa Cornwell in Cincinnati and Ramit Plushnick-Masti in Houston contributed to this report.

Online:

NASA Inspector General report: http://bit.ly/re6odG