Well, my GPA is also at my school's 50% for law school applicants. I can't say that it's negatively affected me thus far.
ETA: I will say that factors that work in my favor are time since the bad grades, a strong upward trend in grades, graduate work, etc. So there are other factors that will balance in. I don't know where you're applying or what your total application package looks like, so it's hard to give you specific advice.