They are the keepers of the information and we are not. They have the power of subpoena, to summon grand juries, to take sworn depositions and to enforce regulatory action. We have no right except that granted every citizen. When in the past the keepers of secrets have told us that damage would occur if we published information, the fears almost never have panned out. All of that strengthens our resolve to publish.
Lawyers are our allies as well as our adversaries, and they can be useful in decision-making.
But they are not journalists and they should not be newsroom decision-makers. The judgment of what is news is an editor's. A lawyer's role is to advise on the law, precedents, behavior of courts, and to rate the risk and outcomes of alternative actions. The best decisions by government follow an instinct for openness, not an instinct for limiting disclosure to only that which a lawyer says is required. You will never find me arguing for government secrecy, but the passion of my opposition will vary according to what I believe is the level of abuse.