My thought is to compare the effects of previous trade agreements on labor rights with the legal protection language offered in the text of the TPP agreement. The sources I have included from Pulitzer, as well as the links below should help us get an idea.
To start, this is a website showcasing the positive impact TPP would have to labor rights:
Now on to those highlighting the negative side:
This is a blog about the perceived negative effects TPP would have on labor rights:
A Q&A on TPP that includes some questions about human and labor rights:
Another article comparing TPP to previous trade agreements to prove the negative impact on labor rights: