The clients really are at fault here.
The lawyers in this case where asked to act within legal and ethical boundaries and within those boundaries they had a duty to act in their clients interest. The final results where unjust, but their actions where fully in upholding their duty.
The results where wrong, but the fault lies elsewhere. In looking for the fault, I would start by looking at the clients (namely the RIAA) that insisted on pursuing this and at the law itself which permits statutory damages so grossly out of proportion to real damages.
In fact, there has been some contention that such high statutory damages may be unconstitutional and I would not at all be surprised if Mr. Camara pursued that avenue.
That's not exactly how a lawyer's professional responsibility is defined. But anyway, as a producer of original writings that have been infringed more than once, I'm glad there are lawyers who work to uphold the copyright laws.