Telia also operate a phone network in Finland, where the state listened in on 3,640 calls last year. Taking into account market share and population, this is more than the number recorded in Sweden, but still five times less than in Estonia.

Lawyer: Difficult to disagree with view that Estonia has become police state

ETV's Ringvaade current events broadcast asked lawyer Oliver Nääs if this means that Estonia is a police state, and if Estonian residents are under stricter surveillance here than they would be elsewhere.

Nääs is very familiar with the state's surveillance and observation tactics, owing to his defence of former long-term Centre Party chairman and Tallinn mayor Edgar Savisaar.

Savisaar stood trial for embezzlement, large-scale money laundering and having accepted illicit political donations, charges that to no small extent based on information gathered by means of Internal Security Service (ISS) wiretaps.

"The numbers published by Eesti Ekspress don't really make any other conclusion possible," Nääs told Ringvaade.

Wiretaps affect population, society on the whole

Nääs pointed out that the awareness of broad-based surveillance and wiretaps has an influence on the population as a whole, infringing on personal freedoms, oppressing people, and at the end of the day having a damaging effect on society.

He further explained that wiretaps have been part of "almost every investigation of a criminal organisation or drug case", and that they have been in wide use also in white-collar crime cases.

To the Office of the Prosecutor General, wiretaps are a convenient way to gather evidence, Nääs said. "You just push the 'record' button and pick and choose later," he added.

"This situation also puts pressure on law-abiding individuals," Nääs said. "They can't speak freely with their friends and family."

Prosecutor Taavi Pern disagrees. According to him, there is no increasing trend in the use of wiretaps, but their number has recently gone down. The process of getting a warrant to tap someone's phone is "sufficiently complicated", though the judges sign off on an average of 90% of the requests.

Surveillance possible and arranged in Estonia without suspicion of crime

Nääs stressed that the Office of the Prosecutor General does not need to suspect someone of having committed a crime to order a wiretap or other surveillance activities.

"There is surveillance for the purpose of counterintelligence. The security authorities actually keep our citizens under surveillance even without any criminal suspicions, but for reasons of national security. We know nothing about it, everything connected to it is a state secret. The extent to which it is carried out also is a state secret, for reasons I at least don't understand at all," Nääs said.

Surveillance for the purposes of counterintelligence, somewhat euphemistically called "information acquisition" (teabehange) in Estonian, allows the Internal Security Service to take surveillance measures for reasons of national security. Just like in the case of a warrant, a judge needs to sign off on it, though none of the people involved in the procedure are allowed to talk about it, and if they do may face charges for having given away state secrets.

Counterintelligence surveillance criticised as intransparent, used for other objectives

On several occasions, the Office of the Prosecutor General along with the Internal Security Service (ISS) used the data request to obtain information they then in turn used to open actual criminal proceedings against individuals. By many accounts, the Savisaar case is an example.

This instrument has been criticised as an intransparent and potentially dangerous component of the Estonian legal system, among other things in connection with the fact that Prosecutor General Lavly Perling's husband, Martin Perling, is a high-ranking ISS officer. Recently retired Judge Leo Kunman has pointed out that there is a lack of oversight of the Office of the Prosecutor General.