Studies indicate that police tend to escalate non-violent situations simply by having pepper spray available:

In one analysis, criminologists found that police use of force rose by 33 percent in Concord, North Carolina following the approval of pepper spray as a law enforcement tool. After an arrestee died in custody after being sprayed, pepper spray use was restricted; use-of-force incidents then fell by 57 percent, even though arrest rates rose by almost 4 percent.

(Image via the tumblr Pepper Spraying Cop)