> ...but "the company reviews each request for data it gets to ensure it is legal" just sounds like something a judge should do, no?

This is assuming the first pass is before a judge. They're circumventing this by going straight to the companies, as noted by the following blurbs:

> This time, DHS utilized a different method that didn’t require approval from a judge, only a sign-off from a DHS official.

and

> It also instructed the recipients of the summons to keep it secret.

In most cases, a company's legal team will attempt to validate the legality of a request because, if they just acquiesce, it becomes a legal problem for them to turn over data without that validation of legality - which can have financial repercussions.

In those cases, the government most often will not (and cannot) step in to save them from the financial blowback (i.e.: the government got what it wanted; it's not their problem, now).