I'll give a very short answer.
Let me give you two concrete examples. I was involved in a complaint filed in Canada regarding the violent--that is, baseball bats and weapons--repression attack on a union organizing campaign in Mexico. Those kinds of situations, or situations that occur all the time--in Colombia, most notably--where trade unionists are murdered when they try to form a union, those sorts of basic, fundamental attacks on freedom of association are exactly the kinds of fundamental abuses that we think this kind of trade regime ought to be able to attack.
If Canada is going to take its human rights obligations seriously, we ought not to be trading with countries where workers who want to associate freely get murdered or beaten up. It's that simple. Those workers should be able to file complaints in Canada about that activity. And then the governments that are failing to protect these workers ought to be held to account for those failures.