968.075 Domestic abuse incidents; arrest and prosecution.
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(2) Circumstances requiring arrest; presumption against certain arrests.
(a) Notwithstanding s. 968.07 (1) and except as provided in pars. (am) and (b), a law enforcement officer shall arrest and take a person into custody if:
1. The officer has reasonable grounds to believe that the person is committing or has committed domestic abuse and that the person’s actions constitute the commission of a crime; and
2. Any of the following apply:
a. The officer has a reasonable basis for believing that continued domestic abuse against the alleged victim is likely.
b. There is evidence of physical injury to the alleged victim.
c. The person is the predominant aggressor.
(am) Notwithstanding s. 968.07 (1), unless the person’s arrest is required under s. 813.12 (7), 813.122 (10), 813.125 (6), or 813.128 (3g) (b) or sub. (5) (e), if a law enforcement officer identifies the predominant aggressor, it is generally not appropriate for a law enforcement officer to arrest anyone under par. (a) other than the predominant aggressor.