A bit of a sad update to this recent post:
https://www.reddit.com/r/smallbusiness/comments/1e01ol1/employing_a_recovered_addict_anything_i_should_be/

Last week the employee in question came in late, asked for an advance on her pay and asked to redeem her vacation pay, which some noted as a warning sign. This week she was abusive towards a new employee, and finally attacked another employee (which she had a relationship with) with a sharp object. She’s been fired.

I don’t want to discourage people from giving people a second chance, but do be realistic about potential issues.