St. Thomas makes rights the object of justice, and they are recognizable as rights in our own sense (e.g. they are divided into natural and legal rights, and slaves as slaves do not have any). One important difference is that, by locating them in the context of justice, rights are properly had by others. It is certainly true that I have rights, but when I say this I am considering them so far as they can make someone else just. To consider rights as my own leaves them recognizable as rights, but it prescinds from the context that could make me a good, virtuous, happy person.
1. Ius (pl. iura) is the object of justice that is true; to translate it as right is potentially misleading since what is meant as ius by St. Thomas is not the same as what we mean by right in the sense of a moral faculty or freedom to do a certain action. It is proper to the Bill of Rights to list these moral faculties in order to safeguard them from being infringed by the Federal Government. The Bill of Rights sets to make explicit the limits to the authority of the Federal Government. [subjective active rights]
2. The other subjective "right," a title or claim to something, may be bound up with St. Thomas's notion of ius. Ius, as explained by St. Thomas, is proper to ethics is moral theology - determining what is owed to another, what must be done/rendered to another (an action, first of all) by a moral agent. Determining what is owed to me is proper to a judge or someone else mediating a dispute, though it is not without the flip side - if I have a legitimate claim to something, then it must be given to me. [subjective passive rights]