The study showed that of Estonian municipalities, the highest risk for corruption was recorded in Tallinn and Vaivara Municipality, while the lowest risk was recorded in Harku Municipality and the city of Maardu, the Ministry of Justice said.

Spokespeople for the ministry explained that the corruption risk index does not refer to actual corruption, but rather evaluates how transparently and openly the municipality organizes public tenders.

The study covered public procurements with a value exceeding €130,000 carried out in EU member states and Norway between 2009 and 2015. On a scale of 0 to 1, Estonia's index was 0.33, above the EU average index of 0.28.

Tallinn and Vaivara Municipality, with the country's highest corruption risk, had indexes of 0.4 and 0.33, respectively, while the lowest index in Estonia, 0.05, was recorded in Harku Municipality.

Commenting on the study, Minister of Justice Urmas Reinsalu (IRL) said that the public sector in OECD countries spends approximately one third of its budget on public procurements, which is also one of the fields most at risk of corruption.

"It is clear that municipalities have not exhausted all existing options for preventing corruption," Reinsalu said. "This is why guidelines are being drawn up which will help municipalities assess and mitigate corruption risks and create their own internal control system with the help of practical examples. New councils to be elected soon can then organize procurements more transparently with the help of these guidelines."

Index based on public procurement transparency

Compiled under the leadership of Mihaly Fazekas, a scholar at the University of Cambridge, the corruption risk index includes five indicators which illustrate the transparency of public procurements: the number of bidders, the type of procurement procedure, the time period between the procurement announcement and the deadline for tenders, assessment criteria, and the time allotted for making decisions.

Compared to others, the most risky examples include procurements with unannounced negotiations as well as procurements with a single bidder, where the amount of time between the announcement and the deadline for tenders is either too long — a reference to legal unclarity — or too short — with the possibility of prior agreements — and the assessment criteria are not measurable.

When analyzing data about Estonia, the Analysis Division of the Ministry of Justice also took into account procurements of municipal institutions. In addition to municipal procurements, the average index may be impacted by the procurements of the municipality's companies and governed bodies, ministry spokespeople noted.

The analysis did not take into account those municipalities with fewer than four tender agreements signed. It must also be taken into account that in the EU public tender database, it is not possible to differentiate between the respective data of municipalities and cities with the same name.