This thesis considers the constitutional questions surrounding the use of force by police officers. When an officer uses force in the line of duty s/he can claim qualified immunity against a lawsuit, as an officer is using force in his or her capacity as a government agent. At the same time, the 4th Amendment protects individuals against unreasonable searches and seizures. The use of force is a seizure of one’s body. Thus there is an inherent constitutional tension when officers use force – should they be protected as agents of the state or should they be punished for violating individual rights? This thesis considers the two different “objective reasonableness” tests that guide courts in determining qualified immunity or 4th Amendment violations. Moreover, it argues that the “objective reasonableness” test is an appropriate test for making this inquiry and it should not be replaced with a proportionality standard, as some have argued. It also considers the role that officers have played in American society and why a use of force continuum is an appropriate training tool that allows officers to carry out their duty as defenders of peace and to stay within the legal safeguards.