The Times reports that the decision came from "federal prosecutors," and that "Justice Department officials concurred with the prosecutors' decision."
The Post, meanwhile, reports:
Prosecutors in New Mexico sent their findings to Justice Department headquarters in Washington, where career prosecutors concluded that an indictment was not warranted...
In other words, both papers attribute the prime decision to non-partisan prosecutors, not to political appointees.
Of course, that hasn't stopped the New Mexico GOP -- not known for its restraint -- from trying to make hay out of the story, asking in a press release: "Was this decision made contrary to the advice of experienced, non-political, career prosecutors and the FBI?"
Based on what we know right now, it looks like the answer is no.