As far as I know - Stafford loans (or the other government loans) do not require a credit check. However, there is a limit on the amount of government loans you can get and it isn't the cost of attending most law schools - going on the assumption that you don't get any scholarships, don't work the first year, and still have "normal" expenses like rent, food, clothes, etc. To make up the difference between the government loans and the cost of living, taking out private loans is the biggest and most used option. For private loans, you typically have a credit check and without good credit you may or may not get them.
The biggest thing that could be a problem, imo, is if you are going to still be paying off what you owe right now while going to school. The cost of living at most schools does not figure in any kind of debt (i.e. car payments, credit card payments, loan payments, etc). If you are making, say $500 a month in payments, that is $500 above the normal cost of living the school thinks you should live on, which is low to begin with - unless you plan on having everything paid off before you start.
My advice, would be to talk to the financial aid counselor at whatever school you are going to. The federal loan limit (I think!!!!) is about 18,500 per year. If you are going to a school that is around 8000 a year plus books and fees - you are looking at a budget of maybe 9000-10000 a year to live off of - roughly 1000 a month if you work during the summer. If you have a lot of payments you are making then that could be really hard... But, then again, if you are going to a night program, living with your parents or someone else that pays the rent, got a scholarship you could be in a much better situation.