The Drug Enforcement Administration paid an Amtrak secretary more than $850,000 over the past 19 years for confidential passenger information, even though the records were available at no cost through an agreement with Amtrak police, according to a watchdog report.

The Amtrak inspector general’s office said the employee handed over the information “without seeking approval from Amtrak management or the Amtrak Police Department.” The report, released in June, said the company removed the worker from service and filed charges against the individual.

Sen. Charles Grassley (Iowa), the ranking Republican on the Senate Judiciary Committee, issued a letter about the matter to DEA chief Michele Leonhart last week, saying the June report “raises some serious questions about the DEA’s practices and damages its credibility to cooperate with other law enforcement agencies.”

The lawmaker requested information on what the DEA is doing about the incident, including whether the agency has identified the agents who were responsible for the payments and whether there are other such cases.

The DEA declined to comment Tuesday on Grassley’s letter or the inspector general’s report.

According to the report, the secretary provided DEA agents with passengers’ “name reservation identification,” which can include travelers’ names, the names of people traveling with them, travel dates, seat numbers, credit card numbers, emergency contact information, baggage information, passport numbers, gender and date of birth.

Under an agreement with the DEA, the Amtrak Police Department provides such information for free in exchange for receiving a share of funds seized through resulting investigations. The report said DEA’s purchase of the records deprived Amtrak police of money the department could have received by supplying the data.

Amtrak is a railroad service that receives large federal subsidies, but it is not a government entity. It operates as a for-profit corporation. The company is subject to the Freedom of Information Act, similar to government agencies.