High treason, a charge used liberally by kings and queens in the Middle Ages, is being vigorously pursued in modern Russia to root out perceived internal enemies.

"It exploded in 2014," said Ivan Pavlov, a defence lawyer based in St. Petersburg, Russia.

At least 15 people were convicted of state treason that year, "triple the average number of previous years," Pavlov said.

"And we expect the numbers in 2015 to show the same."

Russia is fighting a secret war — within its own borders. Amid the already paranoid and militaristic mood that exists inside Russia today, security services are tracking and swooping down on those they consider traitors.

In November 2012, following anti-government protests, President Vladimir Putin strengthened and broadened the criminal code provisions governing treason and espionage — at the urging of the FSB, the country's security service. With the amendments, high treason includes any "financial, material, technical, advisory or any other support given to a foreign country or to international or foreign organizations engaged in activities against the security of the Russian Federation."

Ivan Pavlov specializes in cases of treason, extremism and freedom of information. He is the lead lawyer at Team 29, a St. Petersburg group of activist lawyers and journalists. In 2014, the number of people charged with treason was triple that of previous years, Pavlov said, and has remained high. (Susan Ormiston/CBC )

Human Rights Watch and other critics say the amendments can be broadly interpreted and used as a tool to "justify close surveillance of NGOs and activists … and could also be used to open a criminal case … as a way of paralyzing a critic or political adversary."

The amended criminal code also expanded the definition of state secrets and who could be subject to prosecution.

They (the state) use all their resources to shut down information about these cases so that nobody will know. -Ivan Pavlov, defence lawyer

Treason cases are argued in closed courts with much evidence hidden under the cover of the broad designation of "state secrets."

"They (the state) use all their resources to shut down information about these cases so that nobody will know," said Pavlov.

"They consider independent lawyers who take these cases a point of tension. We expect some actions against us. We have to be ready for them."

Lawyers denied access to evidence

Pavlov is defending Gennady Kravtsov, who was convicted of state treason last September and sentenced to 14 years in a penal colony. Five years after he retired from his job as a radio and IT engineer in the military intelligence service, he sent out feelers for new work. Discouraged with opportunities in Russia, he emailed letters of inquiry to the Ministry of Defence in Belarus and later to a civilian telecommunications company in Sweden. He received no job offers.

Kravtsov, right in conversation with his lawyer, was charged with treason because he inquired about job opportunities with the Belarussian Ministry of Defence and a radio communications company in Sweden. He did not receive any job offers, and his lawyers say he revealed no secret information to foreign entities. (Team 29)

Those emails attracted the attention of the FSB, who raided Kravtsov's home, without a warrant, and took computers and flash drives, according to Kravtsov's wife, Alla Terikhova. Kravtsov co-operated as the FSB watched him for another year. Then one morning, he was seized and put in detention.

"He went to buy milk. They attacked him from behind, threw him on the ground, twisted his arms and started to beat him," Terikhova said.

They attacked him from behind, threw him on the ground, twisted his arms and started to beat him. - Alla Terikhova , wife of Gennady Kravtsov

"Why did they do all this? He knew FSB was watching him. They could have just shown him their documents, and he could calmly follow them. Was it to show they'd captured a spy?"

In a Moscow court, Pavlov and fellow lawyer Evgeny Smirnov asked to see the secret evidence against their client. They were refused. The lawyers cannot specifically quote from the letters Kravtsov sent abroad, because they are considered "secret," but Pavlov insists his client "didn't share any secret information in his letter or after."

The FSB refused CBC's request for an interview on this case or any other treason prosecutions.

"He wasn't an operative. He was just an engineer, an IT engineer," said Pavlov. "The message they sent is that nobody from ex-special services can communicate with any foreign entities. If they do, they will be punished."

'Everything he said they flipped'

Terikhova is bitter and angry. She's left with two small children to raise alone. Kravtsov will serve his time in a penal colony 500 km from Moscow. Terikhova will be allowed two weekend visits a year.

"It's like a witch hunt to show we have spies, [that] we have internal and external enemies," she said.

She says her husband co-operated fully with the FSB and had several meetings with agents. He was sure their inquiries would come to nothing, until the day he was seized.

High treason is being vigorously pursued in Russia to root out perceived enemies of the state. Susan Ormiston meets a team of lawyers who are taking on the difficult cases. 11:46

"Everything he said they flipped," Terikhova said. "They needed his case to show that we have a spy, that there is somebody who will sell his motherland."

In a February speech to the FSB, Russian President Vladimir Putin warned of increasing threats to destabilize Russia internally.

"Foreign intelligence services have stepped up their activity in Russia. It has been convincingly confirmed over the last year," he said.

More than 400 operatives had been apprehended, said Putin, as he urged the security services to keep up vigilance.

Svetlana Davydova, her husband, Anatoly Gorlov, and four of their seven children in their home town of Vyazma. Davydova was arrested in January, nine months after she called the Ukrainian Embassy in Moscow to say she believed troops she saw pass by her house were headed to Ukraine. She was conditionally released in February. (Maxim Zmeyev/Reuters)

"We need to cut off all channels of access to confidential information," he said.

Pavlov believes the Kremlin is creating a climate in which rights and due process can be easily trampled on.

"The government needs some examples of enemies of the people. Everyone understands who is the external enemy: the West, Ukraine. People need to know who is the internal enemy, and that's why government uses the criminal court and the special article about high treason."

Canada's last treason conviction in 1947

Canada has pursued few cases of treason. The last conviction was in 1947. Métis leader Louis Riel, executed in Regina in 1885, is probably Canada's most well-known case. In the U.K., the last prosecution for treason was in 1945.

But in Russia, it's becoming increasingly common.

In January 2015, Pavlov founded his own legal swat team. A group of young lawyers and journalists based in St. Petersburg who call themselves Team 29 after Article 29 in Russia's 1993 constitution, which guarantees freedom of information. Some of the lawyers and journalists who work with Team 29. The group takes mainly cases involving freedom of information, high treason and extremism. (Corinne Seminoff/CBC)

Daria Sukhikh is an earnest and determined 33-year-old lawyer with Team 29.

"We got a brilliant law, the Freedom of Information Act," she said proudly. "It's very progressive."

"[But] we have a problem with it: many rights we have in law don't exist in real life. Good law, bad practise."

Taking on the government isn't popular or profitable. The Team 29 lawyers sometimes work without a salary and rack up more losses than wins.

"Of course, it is very hard work, because courts and the judge are afraid to make decisions against the government," said Sukhikh.

"I get frustrated when I know I have the law on my side, and I'm defeated anyway. But we think we should continue our work because without it, nobody will show the government that this right is important for us."

'How to survive and stay free'

Team 29 has a flash new web site highlighting the cases they've taken on.

Like the case against Svetlana Davydova, a mother of seven children who was opposed to Russia's intervention in Ukraine, who was jailed in January 2015. She had phoned the Ukrainian Embassy in Moscow in April 2014 to report that she believed Russian troops stationed near her home could be on their way to Ukraine, where pro-Russia separatists were clashing with Ukrainian forces.

After vocal protests from some media and high-profile public figures, and a legal defence launched by Team 29, she was released.

Everybody understands that in the 21st century, it's impossible to arrest a librarian for keeping books. - Anna Pavlukova, daughter of librarian charged with distributing extremist literature

Or the charges against Natalya Sharina, director of the Library of Ukrainian Literature in Moscow, accused of distributing "extremist" literature that incites hatred against Russians — books by Ukrainian nationalists, some of them banned in Russia. For five months she's been under house arrest, forbidden from leaving her apartment or communicating with anyone other than her husband, daughter and son-in-law. Charges of embezzlement will be added this week. Sharina denies all charges against her.

"They shame my country; they show the world that we act like people in the Middle Ages," said her daughter, Anna Pavlukova. "Everybody understands that in the 21st century, it's impossible to arrest a librarian for keeping books."

Anna Pavlukova's mother, Natalya Sharina, is under house arrest in Moscow, accused of distributing extremist literature. Sharina is the director of the Library of Ukrainian Literature in Moscow. She is not allowed to step outside her apartment for six months. (Susan Ormiston/CBC )

Team 29 also acts like a public advocate, a novel phenomenon in Russia, posting primers on how to protect oneself.

There's a clickable guide on how to act during interrogation, how to behave during a home search and the most popular post: "what to do when they come for you."

"We tell them first, that the FSB can become interested in them at any moment. Then we try to tell them they have the right to keep silent, to not tell anyone and not to work with a state lawyer because state lawyers sometimes work along with officers of the FSB," said Nikolay Ovchinnikov, a journalist who joined Team 29.

"I'm interested in showing people how to survive and stay free," Ovchinnikov said.

Fighting interrogations, searches and secrecy has become a full time job for the lawyers of Team 29. Recently, Pavlov and Smirnov were able to convince Russia's Supreme Court to reduce the sentence for Kravtsov from 14 to six years.

Three Supreme Court judges recently agreed to reduce Kravtsov's sentence from 14 to six years. His legal team had been hoping for a not guilty verdict but said that's highly unlikely in today's Russia. 'Courts and the judge are afraid to make decisions against the government,' said lawyer Daria Sukhikh. (Susan Ormiston/CBC )

When the ruling came down, Pavlov flashed a thumbs up to Kravtsov's family in court. In their eyes, it was an admission by the court that the evidence against Kravtsov was unsupportable.

"We wanted to prove he's not guilty," said Pavlov. "Of course, we understand with what's happening in Russia, it's not possible, but still, it was the aim."