Charles Lee Tidwell, a 46-year-old mechanic who'd been staying at Kowalski's home, is charged with murder. Tidwell is in the Kerr County Jail on $540,000 bond.
Authorities arrested Tidwell after a traffic stop in which he tried to pass himself off as the 52-year-old Kowalski. An attorney for Tidwell could not immediately be reached for comment.
Kowalski a few months ago invited Tidwell to stay with him, in exchange for working on antique cars the banker collected.
A deputy stopped Tidwell driving one of Kowalski's vehicles.
The officer pulled up Kowalski's photo ID electronically. The image did not match documents that Tidwell offered.
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