Lake Saint Louis, Missouri
A lot of factors could influence the distance a horse traveled during a posse chase. For example, the nature of the terrain would impact the horse’s endurance; so would how hard it was being ridden. The horse also would need feed and water along the way. Eventually, though, even a good horse that was well maintained would tire out during a pursuit.
Butch Cassidy made it even tougher on the law—he reportedly left horses staked out along his escape route, ensuring fresh mounts were available. The chasing posses usually didn’t have that luxury, which was part of the reason Cassidy was never caught after a job with his Wild Bunch Gang (at least in this country).
Posses sometimes chased for days and had to give up. Following the Benson stagecoach robbery on March 15, 1881, a posse that included Virgil and Wyatt Earp and Bat Masterson pursued the outlaws across southern Arizona for nine days of hard riding. At that point, their horses played out. Masterson and Wyatt had to walk 18 miles back to Tombstone.
Marshall Trimble is Arizona’s official historian. His latest book is Wyatt Earp: Showdown at Tombstone. If you have a question, write: Ask the Marshall, P.O. Box 8008, Cave Creek, AZ 85327 or e-mail him at firstname.lastname@example.org