Supporters say that it is only right that officers, who are likely to be confronted by criminals with weapons, should be armed themselves. Detractors claim it leads to more murders than it prevents.
In Britain, there are specially trained firearms police officers who are called upon to attend incidents in which guns are involved and are used to protect VIPs. They do not patrol the streets. It is a system that means instances of the police shooting people are relatively rare.
But in Baltimore, police-involved shootings are not uncommon. So far this year, Baltimore police officers have shot 16 people; the latest a 14-year-old robbery suspect.
