SOFA "Status of Forces Agreement"

New York. In the 1991 Status of Forces Agreement Article XXII, Paragraph 1(a). It states "It is understood under the present state of US Law, the military authorities of United States have no effective criminal jurisdiction in peacetime over members of the civilian component or its dependents" First of all. What is the meaning of the term "no effective criminal jurisdiction"? Does this term mean that the US military loses the right to prosecute civilians who commit criminal acts during peacetime? Please elaborate on the term "no effective criminal jurisdiction" Thanks for your help!!