Surely there are some MP units in the WI Guard. Those backed up by regular infantry with some armor and Bradleys for intimidation would be a heck of a sight to see.
Yes, you have to figure they have some MP units and have at least a brigade of infantry in the WI National Guard. Also, alot of National Guard Infantry units routinely receive crowd control training, with riot gear, night sticks, etc. You have to assume that many of the WI National Guard Infantry units have received crowd control/riot training.
If I was Gov. Walker, and if in fact the police are unwilling to follow my orders or the orders of those acting on my behalf to evict the protesters/agitators from the state Capitol building, I would call up the National Guard and order them to evict and arrest anyone remaining in the Capitol Building after an imposed deadline for the riff-raff to leave has come and gone. Any state workers/teachers/police/firemen arrested by National Guard units would be fired by executive order after a fair, pre-deadline warning has been issued stating they will be fired if arrested in the State Capitol Building after they had been ordered to leave.
After that, I would surround the Capitol Building with National Guard and 'Loyal' police units with orders to keep the marxists riff-raff away from the building. Yes, some Bradleys and Tanks in the background would be a nice sight and possible deterent to the at least somewhat sane riff-raff/agitators that we mean business.