A serious question about the TPP

It's amazing to me how almost nobody pushing the TPP considers the illegal aspects of it, considering how many politicians, including Obama, were lawyers. I'm referring to the parts where a corporation can take a municipality to a court outside the USA and administered by private judges, and declare that municipalitie's regulations illegal, if they harm corporate profits. This question never seems to get asked. Amazing how republicans, who think that the ACA is unconstitutional, are almost 100% behind this trade giveaway. Anyway, those are my thoughts, and maybe someone can set me straight that the TPP doesn't have illegal aspects in it, or that it's not unconstitutional. Thanks.