Everything you need to know about Carter Page, FISA and Donald Trump

President Donald Trump had already seized on the contents of the release as evidence that the entire special counsel investigation into Russian election meddling was a hoax and a witch hunt. Others insisted the FISA warrant showed the process working exactly as it should.

I reached out to Doss to walk me through the FISA process and shed some light on who is right when it comes to the Page warrant in particular. She knows of what she speaks: She spent May 2016 to May 2017 as the senior minority counsel for the Senate Intelligence Committee's Russia investigation and is now the chair of cyber & privacy at the law firm Saul Ewing. She has also previously served as the head of intelligence law at the National Security Agency.

Our conversation, conducted via email and lightly edited for flow, is below.

Cillizza: Let's start simple. Explain the FISA court and how FISA warrants are obtained.

Doss: The FISA process goes back to the late 1970s. During the 1970s, in the post-Watergate era, Congress and the American public were concerned that the US government was spying on Americans, particularly on progressive causes like the civil rights movement and anti-Vietnam War protesters.

After a series of public hearings in Congress -- known as the Church and Pike Committees -- a number of reforms were put in place that would restrict the government's ability to spy on people in the US, and created stricter oversight mechanisms across all three branches of government to ensure that, if the intelligence or law enforcement agencies (CIA, FBI and the like) believed they needed to collect information on specific Americans for intelligence or counterintelligence purposes, the agencies would have to meet very clear standards explaining why they suspected that person was a counterintelligence threat, what information they sought to collect about the person, and how the information would be protected.

The Foreign Intelligence Surveillance Act was a key part of those reforms. Passed in 1978, it created a framework for federal judges to oversee any requests by the government to use electronic surveillance -- wiretapping -- to spy on Americans, and it created a structure of congressional oversight of the executive branch's wiretap requests and transparency for Congress into the decisions by the FISA court. The FISA legislation has complex definitions about what constitutes "electronic surveillance," what it means to be an "agent of a foreign power," and what the process is for approving electronic surveillance in different circumstances.

The law establishes the Foreign Intelligence Surveillance Court (FISC) and creates a set of procedures for federal judges to review the government's requests for surveillance approval under FISA. All 11 of the judges on the FISC are appointed by the chief justice of the Supreme Court. They're all sitting federal judges who are busy with a full docket of cases in their home districts around the country, and they all travel to the FISC courthouse in Washington, DC on a rotating schedule in order to review FISA applications, hear arguments from the government, address any compliance issues that have arisen from FISA matters and issue orders.

Although the judges aren't in Washington full time, the FISC is staffed by fully cleared personnel, including staff attorneys who review all of the applications and can make recommendations to the judge about whether there are novel issues in the application, whether the government should be required to submit additional information, whether a particular application can be decided on the pleadings -- the paperwork -- or should have a hearing where the judge can ask the government questions about the application (including evidence in it), etc. Under the FISA court rules, the judge can direct the government to provide any additional information that the court thinks is necessary in order for it to make a decision.

Finally, it helps to remember which part of the FISA statute we're talking about here. In 2017, there was a great deal of debate over the reauthorization of a different section of FISA, section 702, that deals with collecting communications of non-US persons outside the United States. The documents released on Saturday, however, have nothing to do with section 702. This was an application under Title I of FISA, alleging that a US citizen inside the United States was acting as an agent of a foreign power.

Cillizza: How hard is it to get a FISA warrant? And what about getting it re-upped?

Doss: Getting approval on a Title I FISA application takes a lot of work -- as it should, since an approval allows wiretapping US persons. You can see how much detail and effort goes into these applications just from looking at the documents themselves: the initial application on Carter Page was almost 70 pages long, and -- although some of the information is redacted -- you can see that it includes background information on Russian intelligence operations generally and Russian attempts to influence US elections, as well as the concerns the FBI had about the activities of the particular subject in this application, Mr. Page.

This is much more than just a paperwork drill. All FISA applications go through a lengthy process of approvals within the executive branch as well as in front of the FISC. The details of the process vary according to which section of the FISA legislation is being used to support the application. But the key points for any Title I FISA application are that they go through lengthy internal vetting at the originating agency -- in this case at the FBI. That vetting includes a lot of career FBI agents and lawyers and a supervisory special agent before it gets to the level of the FBI director or deputy director for approval. The same thing happens at the Department of Justice, where working-level career attorneys in the National Security Division review the application before it goes to the head of NSD for approval and then to the attorney general or deputy attorney general.

Once the application is ready to file, it goes to the FISC, where court rules require -- except in emergencies -- that the application be filed at least a week in advance to give the FISC staff attorneys and judge plenty of time to review and determine whether they need additional information, need to have a hearing to ask the government questions in person, etc.

Since this particular kind of FISA authorization is only valid for 90 days, the government is required to come back to court if it wants to continue its surveillance activities. Each time it submits a renewal application, the FBI has to show that there's still probable cause. This usually includes any information from the original application that's still relevant, as well as any new information that the government may have collected, either as a result of the previous FISA order or from other sources.

One of the criticisms of the FISC has been that it approves a large majority of the requests that it receives. However, that doesn't mean that the cases aren't well-supported or thoroughly reviewed. Between the internal processes at the FBI, DOJ, and other agencies who may be involved in a particular order, and the review by FISC attorneys and judges, each application is gone over with a fine-toothed comb. The fact that it's an ex parte proceeding -- that in nearly all cases, only the government is present -- means that the government and the FISC all go to extra lengths to make sure that an application is reviewed in a fair and neutral way to try to eliminate any impropriety or bias.

It's also important to note that there are privacy protections on the back end as well. If a FISA application is approved, the government doesn't get free rein to do whatever they want with the information they collect. The government must handle any information they receive in accordance with minimization procedures that place strict limits on who can see the information, how long it can be kept, whether it can be disseminated, and how it can be used. Both the FISC and Congress oversee how well the government is complying with its minimization procedures.

Cillizza: Now to Page. Tell us the toplines of what we learned from the released documents.

Doss: The most important things we learned are that: 1) the government relied on information developed over the course of several years 2) the Steele dossier was only part of the information relied on by the FBI 3) the government informed the FISC that the dossier information had been developed for the purpose of discrediting then-candidate Donald Trump's political campaign and 4) each time that the application was renewed, the government submitted enough evidence that an impartial federal judge believed there was probable cause to allow the government to continue its investigation.

It's important to remember that the fact that the government was investigating Mr. Page doesn't mean he's guilty of anything -- it means there were a number of questionable activities and circumstances that led the FBI to believe it had a responsibility to investigate. There's been no public statement about what, if any, outcomes there were from that investigation. But you can imagine the risks to national security if foreign intelligence assets were indeed actively trying to infiltrate and influence presidential political campaigns or the administration. Only time will tell whether any of the current investigations conclude that any Americans were knowingly cooperating with Russian efforts to interfere with American politics and democratic process. But -- faced with allegations of the kind in the FISA applications -- the government would be derelict in its duty if it didn't at least pursue these leads to see if there was any substance to them.

Cillizza: President Trump has said this FISA release makes the entire Russia investigation moot. Is he right?

Doss: In order to think clearly about the Russia investigation, it's really important to keep in mind the full context, and to differentiate between what the Russian government did, and whether there were any Americans who -- wittingly or unwittingly -- assisted in that effort.

The President often seems to focus on the question of "collusion" -- whether there were individuals in his campaign or otherwise associated with him who knowingly helped the Russian government with its aims. While those are critically important questions, they're only a subset of the overall questions about what happened in 2016. We know that everyone who has done a thorough, responsible look at the underlying facts has concluded that the Russian government was trying to undermine American elections through a variety of means: through spreading divisive messages on social media using trolls and bots, through attacks on election infrastructure, through hacking and releasing the emails of one of the presidential campaigns.

From last week's indictment of Maria Butina, we know there's also evidence that the Russian government was trying to infiltrate American lobbying organizations like the NRA to influence US politics. The consistent conclusion that we've seen repeatedly from the intelligence community, in the indictments from the special counsel's investigation, and in the statements released by the Senate Intelligence Committee, is that Russia had an aggressive active measures campaign designed to undermine democracy, sow discord, hurt Hillary Clinton and help Trump.

Against that backdrop, even if you assume that none of the concerns the FBI had about Mr. Page bear out, and he was neither wittingly nor unwittingly furthering the aims of the Russian government, we're still left with an overwhelming mountain of other evidence about Russia's efforts to influence and undermine our elections in 2016. So no, I don't think this particular FISA application, or its renewals, are dispositive of the bigger picture.

Cillizza: Finish this sentence: "The most important takeaway from this FISA release is _________________." Now, explain.

Doss: The most important takeaway from this FISA release is that the statutory framework is sound, and the process works.

Because FISC proceedings are classified and oversight is carried out in classified channels as well, many people have a sense of unease about FISA and the FISC. Releasing a FISA application like this is unprecedented, and it's unfortunate that the transparency came about in this way, in the context of a highly charged political environment in which so many people are wondering what information they can trust and how to interpret the information they're seeing. But hopefully the documents provide a window into how FISA actually works in situations like this.

Ever since FISA was passed in 1978, there have been calls for reform and discussions about whether the law strikes the right balance between individual privacy and national security. Those are important debates that we should continue to have. For those who think it's too easy to meet the probable cause standard in FISA applications, then let's have the policy discussion about whether that standard should be changed in the law. But let's not confuse legitimately different ideas about what the law "should be" with a debate about whether the law was applied correctly in this particular instance. The release of these lengthy documents, mostly unredacted, should help everyone -- from law professors to journalists to politicians to everyone else -- better see just how much goes into a FISA application in terms of approvals required, the amount of detail in the application package, etc. Hopefully that transparency will help people make a candid assessment of whether they think the law sets the right bar for the investigation standard, and help reassure them that the current standard is being followed, even in cases like this one that have the potential to be so politically charged.