SACRAMENTO — As high school seniors endure the grueling springtime ritual of college admission decisions, the state auditor on Tuesday released a report affirming the frustrations of many California families: The University of California softened admissions standards for out-of-state students, who pay triple the fees, even as it turned away record numbers of in-state applicants.

The finding — vehemently disputed by UC President Janet Napolitano — adds fuel to an already red-hot debate over which students are admitted to the highly competitive university system, especially at prestigious campuses such as UC Berkeley and UCLA. In the past five years, as their in-state admission rates fell to record lows, the proportion of out-of-state undergraduates at both schools doubled, rising to 25 percent and 23 percent, respectively.

“This is horrific,” said Rohini Ashok, a San Jose parent whose son was rejected from his three top UC campuses last year and enrolled at the University of Michigan. “Someone has to go in there and figure out who is responsible.”

Enrollment of out-of-state students skyrocketed after 2011, when the cash-strapped university system, reeling from state budget cuts, relaxed a policy requiring the scores of non-California applicants to be as good as the top half of admitted in-state students, the auditor’s report found. Now, the out-of-state students need only “compare favorably.”

Napolitano and other UC officials called the auditor’s findings “misleading.” And the university quickly issued its own report aimed at showing that its policies “overwhelmingly” favor in-state students.

The report, Napolitano wrote to the auditor, “makes inferences and draws conclusions that are supported neither by the data nor by sound analysis.”

UC spokeswoman Dianne Klein said in an email that the policy change was “not a lowering of standards.”

“What accounted for the increase in out-of-state enrollment was a 30 percent cut in state funding,” she said.

By the 2014-15 school year, out-of-state enrollment had grown by 82 percent from 2010-11, and UC campuses were collecting $728 million in out-of-state tuition, more than double the amount from four years earlier, said the audit, which was requested by a legislative committee.

The average SAT scores and grades of out-of-state students — while still high — were lower than those of in-state students at most campuses, the report said. And during a 10-year period ending in 2015, the audit found, the university rejected 4,500 Californians whose test scores and grades were at least as good as the average scores for out-of-state students “whom the university admitted to the campus of their choice.”

“Over the past several years, the university has failed to put the needs of residents first,” the report concluded.

The university has acknowledged its growing financial reliance on fees from out-of-state students but contends that they don’t displace in-state applicants. About 60 percent of in-state high school seniors who apply to UC gain admission to at least one campus of their choice, officials say.

Since the state subsidizes the education of UC students, who pay roughly $13,000 in systemwide tuition and fees, state funding — not space — determines how many the system can afford to educate, UC says.

Last year, in response to overwhelming pressure from state lawmakers, the university announced it would make room for 5,000 more in-state undergraduates this coming fall and an additional 5,000 over the following two years. UC has yet to publicize its admission rates for the coming fall.

The audit urges that state lawmakers pass additional legislation, including a cap on new undergraduates enrolled from outside California. One existing bill, from the chairman of the Assembly Higher Education Committee, Jose Medina, would cap UC’s out-of-state enrollment at its current level, 15.5 percent.

“In light of this audit, I question the priorities of UC and their commitment to educating California students,” Medina, D-Riverside, said in a statement Tuesday.

The state auditor said UC — which reviewed the report in advance of its release — disputed many of the findings but found no factual errors.

“We are disappointed that the university objects to many of our recommendations despite clear evidence that improvements are needed,” the report said.

Richard Yao, of Cupertino, said he was troubled by the report — and by a recent meeting with his 11th-grade daughter’s guidance counselor about the difficulty of gaining admission to UCLA and other schools.

“I think most of the kids just want to have a fair shake — if they do get in, they get in for their grades and not for financial reasons,” Yao said.

But not everyone thinks UC is to blame for the shift.

Joseph Thaidigsman, a high school senior from San Diego County who was recently accepted to UC Berkeley, said in an email that accepting some less qualified students who pay more to attend is “an unfortunate but necessary evil.”

“I think this is more of a failure of the government to budget enough money to Berkeley than it is the Berkeley admissions committee greedily sacrificing quality of incoming class to rake in more money,” he said.

Follow Katy Murphy at Twitter.com/katymurphy.