Micah Johnson, Gunman in Dallas, Honed Military Skills to a Deadly Conclusion

Mr. Johnson’s knowledge of “shoot and move” — and the fact that a few of the protesters in the crowd who were not involved in the shooting were armed and carrying rifles — has helped shed light on how a theory of multiple assailants emerged.

In Texas, gun owners can legally and openly carry what are known as long guns, including shotguns and rifles. The carrying of handguns is regulated in Texas and requires a state-issued permit, whether concealed or openly carried, but the carrying of rifles is largely unregulated and requires no permit. The so-called open carrying of rifles has become common at many demonstrations in Texas in recent years.