The episode left Sweeney shaken, and had Stenger officials scrambling to find out who had been following them, according to Bannister’s texts and interviews.

A text from Wagener, the Stenger aide, asked for the license plate. Bannister said he gave the plate to Tom Malecek, an official in Stenger’s administration who had worked for the St. Louis Police Department.

When Bannister and Sweeney left a meeting that day, Malecek “walked up to us and said, ‘Here’s who was following you,’ and handed us a piece of paper and said they had made a traffic stop. And the whole thing just didn’t make any sense.”

Bannister said he was told Clayton police officers pulled over the car, and the plates came back to a telephone consulting company, JM Surveys, registered to a mailbox in Maryland Heights.

Clayton police said they had no record of a traffic stop matching Bannister’s description that day.

Bannister said Wagener asked him to meet Stenger, Malecek and Miller, the chief of staff, later at a restaurant in Clayton.

“And they asked me, ‘Is Sheila OK?’ ... I said she’s pretty shaken up, she wants to know who this was and she wants more information.”