Beginning in 1889, they began "cleaning up" part of what became the State of
Oklahoma. Widely considered honest, dutiful, and capable, they were responsible for suppressing much of the outlaw element in the Indian Territory and environs, reportedly arresting in excess of some 300 desperadoes during the next decade, and killing several others. All three had the reputation of being dauntless in their pursuit, ignoring bad weather, and each was known for their unique tracking abilities. Heck Thomas' relentless pursuit of the Dalton Gang was specifically mentioned by gang member
Emmett Dalton as one reason the
Dalton Gang attempted to rob two banks simultaneously in
Coffeyville, Kansas – to make one big score so that they could leave the territory for a time. Resistance from the lawmen and citizens of Coffeyville to
this robbery ended the gang with the deaths of most of its members. They are most famous for their relentless pursuit of the
Wild Bunch, or Doolin Gang, which included surviving members of the Dalton Gang. The three lawmen eliminated many of the Doolin Gang by systematically killing gang members who resisted them and arresting those who would surrender. Deputy Marshal Heck Thomas killed gang leader
Bill Doolin. Deputy Marshal Chris Madsen led the
posse that killed Doolin gang members
"Dynamite Dan" Clifton and
Richard "Little Dick" West. Deputy Marshal Tilghman was ultimately responsible for the death of Doolin gang member
William F. "Little Bill" Raidler. Other gang members were also captured or killed by them. ==Later years==