I think I see what you're saying, Jerricho. If a pilot follows the ATC instruction instead of the TCAS RA, and the other pilot disregarded the ATC instruction to follow the RA, who's negligence led to the accident? Is it the ATCO (for allowing the aircraft to get that close in the first place), is it the pilot who followed the ATC instruction (for ignoring the RA), or is the pilot who followed the RA (for ignoring the ATC instruction), or is it some combination of all three? What if it was clear day? Would it be different?
Whilst none of us, I dare say, wish to see another such accident happen, it would be interesting to see how a court would handle such a case. If I were to venture an opinion, and this is really what I think Jerricho was getting at, all this new instrumentation (like TCAS, and GPWS even - we haven't really touched on CFIT yet), gives the pilot better information than just looking out the window. It may even be argued that the pilots may even have better "eyes" for the situation than the ATCO, even in full IMC conditions, due to their TCAS.
That argument may even stick better when we consider GPWS, because (and correct me if I'm wrong) a radar controller can't see the height of the terrain, they just have a good idea where it is. In situations where it is found that the pilot had better "eyes" for the situation, the pilot may even be found to be more negligent than the ATCO. However, the ATCO will still share some negligence precisely because they have a good idea where the terrain is, and they shouldn't have let the aircraft even get close to hitting it.
I'm not all that familiar with the accident that involved the TCAS (it was in Germany, wasn't it?), but wasn't it found to be the ATCO's fault? An English, or other Common Law, court may decide to follow that precedent, but they may also see what has changed even since then, and find that the pilots share the negligence because they should have followed the TCAS.
ozm8