Being a project manager is very similar to being a mother. When your child commits a mistakes, gets a bad grade, throws a tantrum in public, you just have to accept it in the face of the public. There is no point in trying to justify to the teacher, or the society on why he/she committed that mistake. Mistake happened, end of story.
How you handle your child, behind the scenes, is up to your style of parenting. The world doesn’t need to know how you do it.
Similarly, as the project manager, you just have to own up the mistakes committed by your team. No client or program manager is interested in hearing you point fingers at your own team. Mistake happened, end of story. Work forward on resolving it. There is no point in working backwards trying to assign blame. Please remember, any day you show your team down, you are actually showing yourself down.