In 1935, Hall, along with a fellow Saskatoon lawyer, Paul G. Makaroff, defended the cases of many of the On-to-Ottawa trekkers against charges brought against them for their part in the Regina riot of July of that year. One police officer, Charles Miller was killed in the line of duty, and a trekker later died of injuries from the riot. Many believed that the trekkers were bolsheviks, but Hall and Makaroff believed that the riot had been provoked by the police. They were successful in having many of the charges quashed. Hall lost friends for his role in defending the trekkers.