It was Easter weekend in 2007 when a police car pulled up to Joe Vasquez’s home in rural Kansas. A doctor had filed a lawsuit against him and his wife over an unpaid $4,561 bill from her emergency hysterectomy three years earlier. They had missed a court date, and the doctor’s lawyers asked the court to issue an arrest warrant. Police took the couple into custody as their grandchildren prepared for an egg hunt, Mr. Vasquez said. They spent two days in jail before their son could borrow the money to post bond."We had no money to pay," said Mr. Vasquez, now 68. At the time, his wife was working at a manufacturing plant and he was on disability, he said. The doctor who sued the couple was Roger Marshall, now a senator from Kansas. Mr. Marshall, a Republican who is seeking re-election this fall, filed lawsuits against more than 700 patients with outstanding bills during his decades-long career as an obstetrician-gynecologist, according to a New York Times analysis of Kansas court records. Patients were arrested in 81 of those cases for missing court dates, the record show. In an additional 13 lawsuits, Mr. Marshall’s lawyers sought warrants but it is unclear whether an arrest occurred. They also garnished patients’ paychecks and bank accounts. They routinely charged patients an 18 percent annual interest rate. The unpaid bills ranged from several thousand dollars to as little as $101. About half the lawsuits were filed under Mr. Marshall’s name and the rest by Heartland Regional OBGYN, the medical practice he solely owned from 1998 to 2012 and then co-owned with another doctor from 2013 to 2019.

Some facing lawsuits were new mothers with outstanding bills from their deliveries. Most lived in Barton County, a rural area with above-average uninsured and poverty rates. Some patients the Times spoke with lacked insurance; others had health coverage but were responsible for part of their bill."I had every intention to pay, I was just struggling," said Kellie Clutts, whom Mr. Marshall sued in 2015 over a $129 bill. Ms. Clutts said the charge was from a postpartum visit shortly after her daughter’s birth. Mr. Marshall sued Ms. Clutts when her baby was 9 months old and eventually garnished her bank account."I was recently divorced, trying to do everything on my own," said Ms. Clutts, 45. "I told them I could make partial payments, but it seemed like no matter what I said, they wanted the full amount at once."

In response to detailed questions from the Times, a spokeswoman for Mr. Marshall said that he spent decades caring for patients regardless of their ability to pay."Judges issue warrants when people repeatedly miss court dates, not doctors," the spokeswoman, Payton Fuller, wrote in a statement. Court records show that Mr. Marshall’s lawyers repeatedly requested arrest warrants, including in Mr. Vasquez’s case. They filed dozens of briefs arguing that warrants were needed because the of the defendant’s “refusal to obey Court orders.”Steven Johnson, a lawyer who often represented Mr. Marshall in debt cases, defended the warrants and ensuing arrests as necessary to ensure that debtors attended court dates."If defendants were allowed to appear only when they wanted to without any consequences the court would get no business done," he wrote in a text message. He said that Mr. Marshall was “no different” than his other clients in allowing his law firm to take the steps they felt were necessary to pursue an outstanding bill. As a client, Mr. Marshall was not involved in decisions about when to seek warrants, arrests, or garnishments, Mr. Johnson said, but did set the 18 percent interest rate in a contract he had patients sign. Mr. Marshall’s office did not respond to a question from The Times about who set the interest rate. Doctors have wide discretion in how to handle unpaid bills. They can decide when to involve a debt collector, file lawsuits or drop the debt entirely if a patient seems unable to pay."There is a lot of variation," said Bar...