The Washington Post just reported this story last night. The FISA Court (for Foreign Intelligence Surveillance Act) is a special court set up to approve warrants required before our intelligence agencies can put individuals in this country under surveillance, like wire taps, etc., for suspicion of working for a foreign power.
There are two categories of those who come under this court: (1) Non-US citizens in this country who are suspected of being agents of a foreign government; those are fairly easy to get approved; and (2) US citizens, for whom the FBI, etc. must present probably cause to think they might be acting as an agent of a foreign power. A judge has to then review the case and decide. This is not a warrant that is easily obtained.
The breaking news is that the FBI obtained such a warrant to put US citizen Carter Page under watch last summer. Warrants are for 90 days and may be renewed, and it reportedly has been, at least once. Carter Page has had an interesting relationship with the Trump campaign. Last year, during the campaign, Trump was asked who his foreign policy advisers would be. The second name he mentioned was Carter Page.
However, Page apparently never had an official position on the campaign, even though he was sort of around on the fringes, his name would come up, etc. A spokeswoman said that he was "an informal adviser." But it sounds more than that; because, while Corey Lewandowski was still campaign manager, Page repeatedly asked his permission to make a trip to Russia. The first time was fairly soon after it was first reported that Russia had hacked DNC emails.
Now Page is a wealthy businessman in the energy business, who has had business dealings in Russia of billions of dollars. He lived in Russia for several years. Why would he need the Trump campaign's permission to go to Russia -- and more than needing it, be turned down by Lewandowski more than once before he finally got permission. What's that about, if he had no connection to the campaign?
This next is known, because Carter Page has acknowledged it himself, that in 2013 he was befriended by three Russian men in New York who wanted to discuss the energy business with him. After several meetings, and at their request, Page supplied them with a report, presumably that he had access to as an insider in the business.
Later, these men were identified by the FBI as Russian spies; and the one still in this country was arrested, tried, and has just finished his prison sentence. They admitted to the FBI that in 2013 they were trying to recruit Page as a foreign "asset" (aka spy). Carter Page apparently was unaware prior to that that they were spies, and he was not charged because, at that point, he had done nothing illegal.
However, in 2016, during the Trump campaign, this same Carter Page was put under surveillance by the FBI. And now information from the warrant that allowed this has been leaked. He has not been charged with anything. News reports have emphasized how unheard of it is for a FISA warrant's mere existence to be leaked. In this case, extensive information about the substance of the waiver request itself has been leaked. So it sounds like some insider wanted to get this information out. Page told the Washington Post reporters that this is simply evidence of the government's spying on people for political purposes.
We do not know whether they have picked up anything about Page or about his links with Russia, beyond that 2013 unwitting episode. Nor do we know whether anything suspicious has been found about the Trump campaign's connections with Russia. But we do know, beyond doubt now, that the FBI is looking.
It is an important development in the investigation into Trump/Russia. The fact that someone has chosen to leak it is significant, because it probably is someone pretty important to have access to the warrant itself.