I could use any resources that any of you have relating to case law for probationary employment. I have a situation developing that could use some legal advice..Thanks..

Not a WI attorney, so I can't help you.
However, you need to say:
About your employer--Public? If so, which government level? Civil service? Type of job? Is there a union? If so, do you have a copy of the CBA?
Private? Union? If so, do you have a CBA copy?
Is there a handbook? Do you have a copy?
Are you a supervisor?

You need to provide much more info.  I would not post anything that might personally identify you, however.

I also posted this in brother of the shield. I am a probationary LEO/non-supervisor. Before you draw any conclusions here (and I know you've all heard this before), but I really haven't done anything wrong and just did my job. My CLEO applied for the same position as me and I was hired instead even though he was higher on the list. I exercised my free speech right very professionally. He got elected as CLEO instead. Since election life has been difficult, and I have been singled out. Department co-workers can and will verify or confirm. Deadline came up and I was terminated...No valid just cause. There are other specifics to that which I can email, but shouldn't post, and other officers WILL confirm. The union said 99% of probation cases they do not take due to difficulties of probationary status. They said this case falls under the 1% and recommended they take it. I'm looking for case law to help in my own defenses and legal actions, and to assist and prepare should the union not be able to represent my interests as well due to the probationary status. I would appreciate any help that anyone knows of..If there are any other questions, I would be happy to answer them either by email or by posting. My email is on my profile I think. Thanks.

Sorry, not a WI attorney.
The problem is that your matter is governed totally by state law, so I can't even give you some hints.
I would ask around to try to find out who is good in state level labor law in your area.
Offer him $100-200 for a conversation about what's going on and some advice. It would be money well spent.