An old Republican rival of Gov. Rick Perry is calling on state and federal officials to investigate whether he broke the law when he began collecting his lucrative pension without actually leaving his job.

Debra Medina, who lost to Perry in the 2010 Republican primary, sent a letter Wednesday to the Internal Revenue Service and the Employees Retirement System of Texas asking for a probe.

“As a taxpayer and a longtime political activist devoted to the protection of public dollars from misuse by government officials, I am concerned that Gov. Perry may be violating the spirit of state and federal regulations related to the compensation of elected officials,” Medina wrote. “Whether or not he violated the letter of these laws remains an open question and is in need of an official and final answer.”

Perry, the longest-serving governor in Texas history, disclosed in recent Federal Election Commission filings that he began collecting his pension in January, boosting his gross yearly income by more than $90,000. Perry still makes his $150,000-a-year salary and has three years left in his term.

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The governor’s aides say he followed rules that allow elected officials to transfer their retirement credits between the “employee class” and “elected class.” But they have not yet provided any paperwork showing what act triggered the retirement.

Perry campaign spokesman Ray Sullivan said Medina publicly backs Perry rival Ron Paul, the Texas congressman who has become a leading contender in Iowa, and is "misstating the facts and state law."

"The law and rules governing elected, employee and judicial class retirement are each unique," Sullivan said in an email to The Texas Tribune. "Perry's actions fully comply with state law (Sec. 813.503 of the Government Code) and ERS rules."

Medina noted that federal rules require that a retirement “results in a termination of employment” and is not accompanied by any promises of re-hire.

She addressed her letter Wednesday to Victor Song, the chief of criminal investigations at the Internal Revenue Service, and to Ann Bishop, executive director of the Employees Retirement System of Texas.

"I ask both of you to conduct thorough reviews of Gov. Perry’s apparent retirement and its associated benefits, and to report your findings to the public as soon as possible,” Medina wrote.

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