What is the legal ruling on the marriage contract if the two witnesses are smokers, one of them is not known to be upright, and the other is not committed to religious observance?

The two witnesses cannot be deemed immoral merely because they smoke, as they may have an excuse. Engaging in an act of disputed immorality does not invalidate one's trustworthiness. If nothing appears from them that would invalidate their trustworthiness, then their testimony falls under the category of testimony by one whose condition is concealed (mastūr al-ḥāl), which is sufficient for marriage according to the Hanbalis. Marriage takes place in villages and deserts, and among common people whose true state of trustworthiness is not known; to consider that (a requirement for validity) would be difficult. The aforementioned contract is valid, and it should be publicized if it has not already been.