A wishy-washy answer means that he is open to amnesty.
A Carson quote:
“Is it moral for us, for example, to take advantage of cheap labor from illegal immigrants while denying them citizenship? I’m sure you can tell from the way I phrased the question that I believe we have taken the moral low road on this issue. Some segments of our economy would virtually collapse without these undocumented workers—we all know that—yet we continue to harass and deport many individuals who are simply seeking a better life for themselves and their families.”