The Wisconsin Judicial Commission, the body that overseas judges and lawyers in Wisconsin, has charged Justice David Prosser with three charges, the most serious being judicial misconduct.
Here is the applicable statute where Prosser is being charged under:
757.81(4)
(4) "Misconduct" includes any of the following:
(a) Willful violation of a rule of the code of judicial ethics.
(b) Willful or persistent failure to perform official duties.
(c) Habitual intemperance, due to consumption of intoxicating beverages or use of dangerous drugs, which interferes with the proper performance of judicial duties.
(d) Conviction of a felony
Prosser has been charged under (4)a: willful violation of judicial ethics for, according to the complaint, forcibly puting his hands on Justice Bradley's neck and for calling Chief Justice Abrahamson a "total bitch."
As you can see from the other items under "misconduct," including conviction of a felony, misconduct is a very, very serious charge.
The catch, though, is that the Supreme Court must decide on the punishment. If this were a circuit court judge being charged with misconduct, that judge would most certainly be removed from the bench, but given the partisan nature of the Wisconsin Supreme Court it is unlikely that any conservatives will rule in favor of any type of punishment for Prosser.