Gun control, homicide rates not linked: study - Criminal record checks, 28-day waiting periods, the long-gun registry: none has done anything to stem Canadian firearm homicide rates, according to a new study by an emergency-medicine academic.  “No significant beneficial associations between firearms legislation and homicide or spousal homicide rates were found,” reads the abstract on the study, written by Caillin Langmann, a resident in the division of emergency medicine at McMaster University, and himself a vocal foe of gun-control measures who has argued instead for enhanced social programs to combat the causes of gun violence.