In an exclusive U.S. TV interview, Edward Snowden said he would like to return home but that the U.S. won't agree to a fair trial.

"I would like to return to the United States. That is the ultimate goal. But if I'm gonna spend the rest of my life in prison, the one bottom line demand that we have to agree to is that at least I get a fair trial. And that is the one thing the government has refused to guarantee because they won't provide access to what's called a public interest defense," Snowden told "CBS This Morning."

The former NSA contractor is shedding new light on his decision to reveal classified documents about the U.S. government's mass surveillance program back in 2013. Snowden disclosed government programs that collected Americans' emails, phone calls and internet activity in the name of national security and was subsequently charged under the Espionage Act for doing so. A congressional report said his disclosures "caused tremendous damage to national security."

In his new memoir, "Permanent Record," Snowden tells his story in detail for the first time and speaks about his life in exile in Russia. Snowden, who now identifies himself as a privacy advocate, said his biggest issue with standing trial in the U.S. is that the government won't allow the jury to consider his motivations.

Edward Snowden CBS News

"Again, I'm not asking for a parade. I'm not asking for a pardon. I'm not asking for a pass. What I'm asking for is a fair trial. And this is the bottom line that any American should require. We don't want people thrown in prison without the jury being able to decide that what they did was right or wrong. The government wants to have a different kind of trial. They want to use special procedures they want to be able to close the courtroom, they want the public not to be able to go, know what's going on. And, essentially, the most important fact to the government and this is the thing we have a point of contention on, is that they do not want the jury to be able to consider the motivations. Why I did what I did. Was it better for the United States? Did it benefit us or did it cause harm? They don't want the jury to consider that at all. They want the jury strictly to consider whether these actions were lawful or unlawful, not whether they were right or wrong. And I'm sorry, but that defeats the purpose of a jury trial," Snowden said.

When pressed on whether he considers what he did unlawful, Snowden refused to take a position but said "it's not hard to make the argument that I broke the law." He went on to say that the government continues to allege that his disclosures caused harm but, according to Snowden, has yet to show evidence of that harm.

"They never show evidence for it even though we're now more than 6 years on, it would be the easiest thing in the world to show. We've never heard that story," he said. "If they had some classified evidence that a hair on a single person's head was harmed, you know as well as I do, it would be on the front page of The New York Times by the end of the day."

Snowden also took issue with the common refrain that leaking classified documents violated the oath of secrecy he took upon entering the CIA. He said an oath of secrecy does not exist.

"One of the common misconceptions in one of the earlier attacks, that we heard in 2015, that we don't hear of so much anymore is that I violated this oath of secrecy. That does not exist. There is a secrecy agreement, but there is also an oath of service. An oath of service is to support and defend, not an agency, not even the president, it is to support and defend the Constitution of the United States of America against all enemies – direct quote – foreign and domestic. And this begs the question, what happens when our obligations come into conflict."

In a statement to CBS News, the NSA said: "Edward Snowden violated his lifetime obligation to protect classified information and betrayed the trust of his coworkers and the American people."

We also reached out to the CIA and Department of Justice to respond to Snowden's book. They declined to comment.

Below is a transcript of Snowden's full interview with "CBS This Morning":

GAYLE KING: Now you said in the book you wish you had a strategy in terms of a what's next plan once you released those documents. You sit here six years later, in exile in Moscow – where you say you don't want to be — was it worth it?

EDWARD SNOWDEN: It was. I mean when we look at all of these complexities and all of the consequences that we have as a result of any of the decisions that we go through in our lives. I think we realize that, look we see chances, opportunities in life when we get the chance to do something. And right now, in 2019, it's hard to look at the world and think nothing needs to change. But nothing changes just if we believe in something, we have to actually be willing to risk something. We have to actually be willing to stand for something.

KING: But you took an oath to the Constitution, Edward. You took an oath not to betray the country. You know the CIA has what you call an orientation, and indoctrination program, where they have a parade of horribles. And now you are on the list of parade of horribles, your picture is there.

SNOWDEN: Probably, yes, but that is actually an important point. I was required to swear into oath when I entered into duty in the CIA. It is a very solemn thing. You are in a darkened room in front of a flag, everyone else is there. But it is important to notice that we did not say an oath of secrecy. One of the common misconceptions in one of the earlier attacks, that we heard in 2015, that we don't hear of so much anymore is that I violated this oath of secrecy. That does not exist. There is a secrecy agreement, but there is also an oath of service. An oath of service is to support and defend, not an agency, not even the president, it is to support and defend the Constitution of the United States of America against all enemies — direct quote — foreign and domestic. And this begs the question, what happens when our obligations come into conflict, right? What happens when you have a secrecy agreement, but you have also witnessed your own government, your own agency, your workplace, violating the rights of Americans, and people around the world on a massive scale.

ANTHONY MASON: Edward, this is a very personal book, Mr. Snowden. And as you've pointed out, growing up in the intelligence community, and your parents were in government. It wasn't easy for you to become personal here. But, I am curious, since you grew up in a community where almost everyone was somehow connected to government service, many of them FBI, did you approach your family at all about this? How did they react to it when you went through this process and how do they feel about it now?

SNOWDEN: This was actually one of the hardest parts of coming forward, was that I couldn't talk to anyone about it. Because this is the bizarre sort of circumstance is the way that our laws are currently structured. In 2013, I was a contractor working for the NSA through a private company. I worked in the NSA facility, I had an NSA boss, I was working at NSA systems, doing NSA tasks. But, formally, just on paper, I worked for a private company. Now these contractors weren't covered by whistleblower protection laws. If I had tried to talk to a judge, a priest, a congressman, it would've been the same felony. If I talked to my family, it would've been the same felony. And of course, if I talked to a journalist, they considered telling the truth about talking about the government breaking the law is in itself a crime. And so, I couldn't tell anyone. I couldn't tell the love of my life, who is a central figure in this story, Lindsay Mills, my long time partner. Because if I had, the FBI could have charged her, as a part of the conspiracy. They could have charged her as sort of an accessory to the crime, so long as she didn't immediately after hearing from me, you know I'm thinking about talking about journalists, picked up the phone and said help, help, someone is going to talk to the press. And so that made it a very isolating experience.

TONY DOKOUPIL: Edward, your formal employer at the NSA said they couldn't comment on your book because ongoing investigation. But, they did give us the following statement: Edward Snowden violated his life time obligation to protect classified information and betrayed the trust of his coworkers and the American people. Edward, do you acknowledge that you broke the law and that there are many people in this country that see your actions as traitorous?

SNOWDEN: Well, I won't take a position on whether or not I broke the law because that's one for the lawyers. But what I will say is this. You know, it's not hard to make the argument that I broke the law, and I think that's actually the less interesting question. It's funny that whenever the government comes after me they say, you know, these disclosures cause harm. But they never justify the harm, they never show evidence for it. Even though, we are now more than six years on, it would be the easiest thing to show.

DOKOUPIL: To be fair, sorry to break in there. But on the question of harm. I don't know that you're, forgive me, but how are in a position to judge the harm in your disclosures. Isn't that something that the intelligence community would be uniquely situated to gauge.

SNOWDEN: Well, I would argue, that I worked for the US intelligence agency for a long time. I am the only one who knows the actually documents that the journalists have, and the ones that they published. We all know, and so it's available to all of us to assess the harms. And again, if they had some classified information. If they had some classified evidence that a hair on a single person's head was harmed, you know as well as I do, it would be on the front page of The New York Times by the end of the day. Because, leaking is not something that only happens to the people that are working to inform the press that are doing. It is also what the government does to sort of backstop their positions. They are authorized leaks, that happen all the time. That are not public interest whistleblowing, right. But back to that question of did I break the law. Again, what's the question that's more important here? Was the law broken or was that the right thing to do? If you look back at the history of the United States, it doesn't take very long for the average person to think about a moment in which it was absolutely illegal to do something. But at the same time, it was absolutely the same thing to do.

MASON: You're living in Russia and have for some time now. As you've pointed out it's not where you want to be, it's where you're forced to be. Have the Russians ever asked for any information from you?

SNOWDEN: This is actually a big scene in the book as soon as I landed. And for the audience that might be less familiar with the story, it was never my intention to be in Russia. I was actually transiting en route to Latin America. The United States government, for some reason — we don't know if it was intentionally to create kind of an evergreen political attack against me, guilt by association to be able to point to the Russian government — or they simply panicked when they saw that I might be, what they considered, escaping. They canceled my passport. When I landed, I could no longer travel. So I get pulled out of passport control and brought into a room. And yes! Directly. The Russian intelligence service was like, "do you want to cooperate? Do you have any information? Life is going to be very hard if you don't have anyone on your side." And I said "look, that's not how this is going to be. That is not how this is going to work. I do not have any information. You can search my bag if you want, because I destroyed my information before I got on the plane." I think that was probably what they expected, because remember, there's about 4,000 journalists downstairs looking for me in this airport at this moment. I'm on every tv channel, I'm on every newspaper. And I was just trying to continue on my journey into asylum. The reason that you know this actually happened, because you might be skeptical, you might think, "Oh, well the Russians are just going to let this guy go." Russia has, uh, shall we say, a problematic human rights record, at a minimum. That's if we're being generous. When we look at the opportunities they have to do the right thing on the international stage, it seems pretty few and far between. But here's a circumstance when they don't have to do anything to do the right thing. All they have to do is not hand me over. Even despite the fact that Russia was, probably, the hardest place in the world for the CIA to operate. I didn't go, "alright, this is great, let me out of the airport." I was stuck in that airport for 40 days—

KING: Do you have concerns, Edward, that—

SNOWDEN: 27 countries in the world—

KING: Russia is monitoring your actions today? Do you have concerns that they're gathering intelligence on you? Because the optics, as we sit here in America, looking at you in Russia, you know, the optics are not good.

SNOWDEN: No, you're absolutely right. You and I are on the same side on this issue.

DOKOUPIL: Then why don't you come home, Mr. Snowden?

SNOWDEN: One of the big topics in Europe right now is should Germany and France invite me in to get asylum—that's how they're handling the response to this new book. But when you look at that kind of thing, of course it's problematic. Of course I would like to return to the United States. That is the ultimate goal. But if I'm going to spend the rest of my life in prison, then one bottom line demand that we all have to agree to is at least I get a fair trial. That is the one thing the government has refused to guarantee because they won't provide me access to what's called a "public interest defense."

DOKOUPIL: But Mr. Snowden—in all due respect—

SNOWDEN: Go ahead.

DOKOUPIL: Mr. Snowden, in all due respect, criminals and alleged criminals barely get to decide the terms of their trial. They broke the law and they face the consequences. What makes you different?

SNOWDEN: Well I'm not different. Again, I'm not asking for a parade. I'm not asking for a pardon. I'm not asking for a pass. What I'm asking for is a fair trial. And this is the bottom line that any American should require. We don't want people thrown in prison without the jury being able to decide that what they did was right or wrong. The government wants to have a different kind of trial. They want to use special procedures. They want to be able to close the court room. They want the public not to be able to know what's going on. And essentially, the most important fact to the government, and this is the thing we have a point of contention on, is that they do not want the jury to be able to consider the motivations — why I did what I did. Was it better for the United States? Did it benefit us? Or did it cause harm? They don't want the jury to be able to consider that at all. They want the jury strictly to consider whether these actions were lawful or unlawful not whether they were right or wrong. I'm sorry but that defeats the purpose of a jury trial.

KING: You were able to steal 1.5 million documents which is an astounding number, do you think that could be done today?

SNOWDEN: First off that's not correct (laughs). That's the government's number. And all of the journalists that have been handling this archive for years have said that's not accurate.

MASON: What is the number?

SNOWDEN: I think that's especially troubling—

KING: Yeah, what is the number?

SNOWDEN: Well, you're asking a privacy advocate for private information. Of course that's not going to go very well. But good try. What I will say is this: I gathered a lot of information about what I believed was evidence of criminal activity on the part of the United States government's unconstitutional programs. And simply, things that were problematic—that were ethically questionable. And I provided these to journalists. And this is critical here—the number of documents that I published is zero. So when the government says 'I caused harm' what do they mean by that? What they mean is the press, having access to things the government didn't want the public to know, decided and made an institutional judgement and these are some of the most trusted institutions in journalism, like The Washington Post. And these guys said "the public has a right to know this," and I required them as a condition — these journalists — as a condition of access to this archive of material, to make an agreement that they'd publish no story simply because it was interesting, no story simply because it was newsworthy. They could only publish stories they said were in the public interest to know. And as an extraordinary measure on top of this, to sort of reconstruct the system of checks and balances that have failed internally in government between the executive and legislative and judicial branches, the journalists would then in advance of publication, warn the government about the story they were about to break. They would give the government an adversarial stage in the process and argue against this, saying "you guys don't understand this," or "Snowden's a liar," or "these documents are fake," or even if it's absolutely right, somebody will be hurt as a result of this, and so they could always make these arguments in the publication process. As far as I understand, this process was followed for all the publications. And that is why I am so confident now, in 2019, that despite the evergreen sort-of allegations of government, whenever any whistleblower comes up, they say, "it causes harm, it causes harm, it causes harm," we have never seen any evidence of that. And just one last point on that — because I think it is especially critical. Just remember the history of this — we have always seen that in this country. When the country — not the country. When the government is embarrassed after being caught breaking the law, they say the people who revealed that lawbreaking have caused serious harm to national security. This was the case of Daniel Ellsberg way back in the Vietnam War with the Pentagon Papers which was the classified history of the government's role in Vietnam. Now Ellsberg—

KING: Alright—

SNOWDEN: when Ellsberg revealed this they said he was the most dangerous man--

GAYLE KING: We can't go back into that history.

SNOWDEN: No, no, no, we are not going back.

KING: Wrap it up.

SNOWDEN: It's just a central point.

KING: Yes you are.

SNOWDEN: It's just a central principle here. What harms the country? Is it a war built on lies? Or is it the revelation of those lies? Is it the construction of a system of mass surveillance that violates our rights? Or is it the revelation of that by the newspapers that we trust? If we can't trust newspapers, if we can't agree on the basic facts and then have a discussion, about whether this was right or wrong, not what's lawful or unlawful, we're losing our position as a democracy and as a government that is controlled by the people—rather than people that are controlled by the government.

KING: Alright Edward Snowden, it's interesting you said newspapers released it, but you gave the information to the newspapers to release, minor detail there. We thank you very much for taking—

SNOWDEN: Absolutely.

GAYLE KING: We thank you for taking the time.

SNOWDEN: Absolutely.

KING: The story's not over. Thank you.