Redford's office said it needed to make sure she got back in time last spring for Ralph Klein's memorial service and wind shear had grounded one direct commercial flight to Calgary days earlier.
The cost of flying the government plane down empty and returning with Redford, her daughter and two bodyguards was $9,200.
"Premier Redford was required to cut short her personal vacation with her daughter to attend former premier Ralph Klein’s official memorial," Redford's spokeswoman Neala Barton said Friday in an email.
"Commercial flight options were considered. Of note, there were news reports of significant challenges with getting passengers out of Palm Springs at the time, involving WestJet Airlines."
Barton said Redford and her daughter had flown down to Palm Springs on a commercial flight at their own expense.
Wildrose finance critic Rob Anderson noted that passengers on the grounded WestJet flight had already arrived home, using a second plane, well before Redford left Palm Springs on April 3 for Klein's memorial service April 5.
"How can they blame it on a weather delay that happened three days earlier?" said Anderson in an interview.
"There's so many questions that don't add up here."
He said it would be different had there been a last-minute problem. But Redford had a six-day window between Klein's death March 29 and his memorial service to arrange a much-cheaper commercial flight back, he said.
"She consciously waited until a couple of days before the funeral and had the government aircraft fly them out when there were perfectly good options that were way cheaper.
"She's not being truthful, and she's misusing government resources."
NDP Leader Brian Mason agreed that Redford had cheaper options. He also questioned why she needed two bodyguards while she was relaxing in an upscale U.S. resort.
"I'm very puzzled by the requirement for two security guards to be with her while she's on vacation. There's very little reason for a security risk when you're in a place like Palm Springs," he said.
Redford has already been under fire for spending $15,000 on a government plane in December to fly to Ottawa to catch another plane with Prime Minister Stephen Harper to South Africa for Nelson Mandela's funeral.
The total bill for Redford and her aide, Brad Stables, was $45,000. That included $20,000 worth of first-class tickets for Stables and a $10,000 first-class ticket for Redford to get back.
Nova Scotia Premier Stephen McNeil took the same trip for under $1,000.
Redford's office initially said that commercial flights to South Africa were not an option. When evidence later surfaced of two commercial flights going at the same time as the government plane, Barton said only one option was made available to staff and they were concerned that flight would be delayed in Toronto for de-icing in -3 C temperatures.
Redford has apologized for the cost of the South Africa trip. She has said her staff didn't follow travel protocols, but she has refused to pay any of the money back.
Anderson said a theme is emerging of a premier who preaches fiscal prudence at home but seeks flimsy excuses to ditch commercial flights and buzz about North America on a government plane at much higher costs.
"It's a pattern now. She clearly could have flown back commercially but decided to do something that was 10 times the cost," he said.
Redford has also been questioned about allowing Calgary-based Stables to bill taxpayers $200 a night at the high-end Hotel Macdonald when he stays overnight in Edmonton. Her office has said it's value for money because it is a cut-rate price.
Critics say Redford needs to economize and start leading by example, given that her last budget held the line on spending and slashed money for post-secondary education. She has also negotiated lean wage deals with doctors and teachers and is trying to do the same with other public-sector workers.
One of the slogans of her government is "living within our means."
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