In July 2010, Lt. Governor Peter Kinder filed a lawsuit, with three other Missouri residents, challenging the federal health care law. The suit asserted concerns about violation of the U.S. Constitution, the Missouri Constitution, and creates unfunded mandates for the state. It contained eight counts. While many Republicans backed the lawsuit politically, there looked to be legal hurdles for the suit. One analyst told Missouri Watchdog he expected at least half of the claims would be dismissed.

Kinder filed a memorandum in opposition to the attempts by the federal government to dismiss his constitutional challenge. Kinder said the move by the U.S. Department of Justice to try and get his lawsuit in federal court dismissed was a "desperate ploy."

Reaction to Cuccinelli's results

Kinder commended U.S. District Court Judge Henry Hudson in Virginia for his ruling that the mandate to buy health insurance — a key provision of the federal health care reform law — was unconstitutional.

“Today’s ruling is a victory not only for the people of the United States, but also for the freedoms we hold so dear,” Kinder said. Judge Hudson found that the federal government could not force individuals to buy health insurance. “Judge Hudson’s ruling confirms what many of us believed to be true nearly one year ago; that Congress overstepped their authority in mandating that every American purchase health insurance,” Kinder said. He said that the ruling boosted the efforts of 20 states that would soon after bring similar legal arguments before another federal judge in Florida.

A audit report in December 2010 claimed that staff members in Kinder's office failed to verify the mathematical accuracy of time sheets. They also did not get independent approval of purchase transactions. The information was not verified when time sheets were approved, according to the audit report released by Missouri Auditor Susan Montee. In one instance, auditors uncovered 32 hours of used compensatory time that was added to the balance instead of subtracted, resulting in an overstatement of 64 hours. For one employee, the time sheet sick leave balance was 10 hours greater than the balance on SAM II, the state’s integrated financial, human resources and payroll system. “To help ensure mathematical accuracy, the office should consider an electronic time sheet which calculates the ending balance for leave and compensatory time,” according to the late 2010 audit report. “In addition, leave slips should be reconciled to time sheets, and time sheet leave balances should be reconciled to SAM II balances on a periodic basis.”

During his first gubernatorial race in 2011, Kinder took a "selfie" with a former stripper, Tammy Chapman, in a St. Louis bar known for its "pantsless parties." Amid the ensuing controversy, it came to light that Kinder had frequented a strip club during his time as a state senator. According to Chapman, Kinder showered her with gifts and letters, but his affections were not reciprocated. She claimed that Kinder became "aggressive" with her, leading her to cut off contact with him. In 2011, Chapman encountered him in a St. Louis bar where she worked. Chapman and the bartender claim that Kinder asked Chapman to come live with him in an apartment that was paid for by his campaign. Chapman declined, telling Kinder that she was gay. Kinder reportedly left after taking a picture with Chapman.

In 2011, the St. Louis Dispatch reported that Kinder had used approximately $35,000 of taxpayer money on personal trips, including sporting events, social galas, and several tea party rallies. Without admitting any wrongdoing, Kinder agreed to pay the state $35,000 to reimburse the cost of the travel in question.

Missouri State Senate (1992-2004)

In 1992 Kinder made his first bid for public office, winning election to a seat in the Missouri State Senate representing Cape Girardeau and surrounding counties. Kinder was re-elected in 1996 and 2000. He considered running for state auditor in 1998, attorney general in 2000, and governor in 2004, but ultimately passed each time. When the Republicans gained a majority in the Missouri Senate following a round of special elections in February 2001, Kinder became President Pro Tempore, the top official in the Missouri Senate.

In 2004, Kinder won election as Missouri's Lieutenant Governor, defeating Democrat Bekki Cook. He re-elected in 2008 and 2012. He sought re-election in 2016, but was defeated in the Republican primary.

Despite having launched an exploratory committee in September 2013, Kinder announced on November 1, 2013, that he would not challenge Rep. Jason Smith for the Republican nomination to Missouri's 8th Congressional District.

Healthcare lawsuit

In July 2010, Lt. Governor Peter Kinder filed a lawsuit, with three other Missouri residents, challenging the federal health care law. The suit asserted concerns about violation of the U.S. Constitution, the Missouri Constitution, and creates unfunded mandates for the state. It contained eight counts. While many Republicans backed the lawsuit politically, there looked to be legal hurdles for the suit. One analyst told Missouri Watchdog he expected at least half of the claims would be dismissed.

Kinder filed a memorandum in opposition to the attempts by the federal government to dismiss his constitutional challenge. Kinder said the move by the U.S. Department of Justice to try and get his lawsuit in federal court dismissed was a "desperate ploy."

Reaction to Cuccinelli's results

Kinder commended U.S. District Court Judge Henry Hudson in Virginia for his ruling that the mandate to buy health insurance — a key provision of the federal health care reform law — was unconstitutional.

“Today’s ruling is a victory not only for the people of the United States, but also for the freedoms we hold so dear,” Kinder said. Judge Hudson found that the federal government could not force individuals to buy health insurance. “Judge Hudson’s ruling confirms what many of us believed to be true nearly one year ago; that Congress overstepped their authority in mandating that every American purchase health insurance,” Kinder said. He said that the ruling boosted the efforts of 20 states that would soon after bring similar legal arguments before another federal judge in Florida.

Errors in time records

A audit report in December 2010 claimed that staff members in Kinder's office failed to verify the mathematical accuracy of time sheets. They also did not get independent approval of purchase transactions. The information was not verified when time sheets were approved, according to the audit report released by Missouri Auditor Susan Montee. In one instance, auditors uncovered 32 hours of used compensatory time that was added to the balance instead of subtracted, resulting in an overstatement of 64 hours. For one employee, the time sheet sick leave balance was 10 hours greater than the balance on SAM II, the state’s integrated financial, human resources and payroll system. “To help ensure mathematical accuracy, the office should consider an electronic time sheet which calculates the ending balance for leave and compensatory time,” according to the late 2010 audit report. “In addition, leave slips should be reconciled to time sheets, and time sheet leave balances should be reconciled to SAM II balances on a periodic basis.”

Relationship with former Penthouse model

During his first gubernatorial race in 2011, Kinder took a "selfie" with a former stripper, Tammy Chapman, in a St. Louis bar known for its "pantsless parties." Amid the ensuing controversy, it came to light that Kinder had frequented a strip club during his time as a state senator. According to Chapman, Kinder showered her with gifts and letters, but his affections were not reciprocated. She claimed that Kinder became "aggressive" with her, leading her to cut off contact with him. In 2011, Chapman encountered him in a St. Louis bar where she worked. Chapman and the bartender claim that Kinder asked Chapman to come live with him in an apartment that was paid for by his campaign. Chapman declined, telling Kinder that she was gay. Kinder reportedly left after taking a picture with Chapman.

Repayment of taxpayer money used for personal business

In 2011, the St. Louis Dispatch reported that Kinder had used approximately $35,000 of taxpayer money on personal trips, including sporting events, social galas, and several tea party rallies. Without admitting any wrongdoing, Kinder agreed to pay the state $35,000 to reimburse the cost of the travel in question.

In 1992 Kinder made his first bid for public office, winning election to a seat in the Missouri State Senate representing Cape Girardeau and surrounding counties. Kinder was re-elected in 1996 and 2000. He considered running for state auditor in 1998, attorney general in 2000, and governor in 2004, but ultimately passed each time. When the Republicans gained a majority in the Missouri Senate following a round of special elections in February 2001, Kinder became President Pro Tempore, the top official in the Missouri Senate.