Salt Lake City Police Department
- March 1983 SWAT magazine article “How Close Is Too Close?”
- Tueller Drill is a self-defense training exercise
- 21 Foot Rule – an attacker with a knife could cover 21 feet before you can draw
- Armed Citizens’ Legal Defense Network, Inc.
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https://armedcitizensnetwork.org/the-tueller-drill-revisited
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- Glock Armorer Instructor