To keep this simple, No joint accounts what so ever until everything caught up. Creditors can and will garnish any joint assets, even if your the only one putting money in it. Just because they haven't yet, doesn't mean the next creditors that buy the debt will not. Do you really want the liability of joint credit when her past due bills have not been paid? If god forbid she dies, you pay. Divorce? You pay. What the divorce judge orders is not binding on the creditors and you will be paying the debt to save your score if she can't or won't . If any student loans, taxes or child support is past due, NO joint returns. They will intercept the refund without advanced warning.
Even if he did not get a joint accoint with his wife they can still get the money from him other ways taxes, his accounts etc...because even if they garnish her accounts the next step will be she is ging to have to use his accounts to pay household bills. Once you have decided to marry a person youtake on everything about your significant other. To get a handle on your bills and to tackle her debt I would suggest you get a joint account and the both of you get a separate account each. The joint account will handle all household bills and all of your debt. Come up with a common goal and you guys should be fine. It might sound unfair, but as stated before this is something you both should have discussed before you got married.