That would be ridiculous, since that is not the argument that needs to be made. Instead, you want a logical argument as to why the concept of collective bargaining in the public sector is a bad one. I won't provide one since they are readily available if you have an ounce of curiosity. I'll just leave this:
βIt is impossible to bargain collectively with the government.β - George Meany
Look at the union-born gigantic pension issues in California and Illinois. http://www.illinoispolicy.org/blog/blog.asp?ArticleSource=60... or http://articles.chicagotribune.com/2011-01-29/news/ct-met-su...
Check out what unions did/do to convention centers in Chicago and Las Vegas. http://articles.chicagotribune.com/2012-01-17/business/chi-0...
Look at the pay of BART employees. http://www.mercurynews.com/salaries/bay-area?Entity=Bay%20Ar...
Or is that all just anecdotal as well? I could go on.