Barry Eisler, a former CIA agent turned novelist, has put forth a handy checklist that journalists can use to determine just how co-opted they have become by the very powers over which they are supposed to be serving as a watchdog. It can help any reporter decide just how far down the road to hackdom they've traveled so far. It's like one of those online personality tests, but it tells you exclusively how much of a sellout you are.
First comes a small ethical compromise. Then larger and larger rationalizations. A loss of self-awareness. An increasing identification with your sources. It's all a very natural process. It happens in slow stages. Even in the midst of its deleterious effects, it may be difficult to detect at all.
2. As the compromises accumulate, you'll need a larger, more all-purpose rationalization to explain them away. I suspect the most common of these boils down to, "Okay, this isn't my proudest moment, but overall I do more good with my journalism than I do bad. Plus, if I left this position, it would be filled by someone with (even) greater capacity for compromise, and less capacity for doing good. So on balance, I have to do this small bad thing in the service of the larger good I do."