Five and a half years after Belgian and French police managed to crack Sky Phone encryption and collect millions of messages, leading to the arrests of hundreds of drug cartel members and the seizure of drugs, weapons and money, courts across Europe have begun to take different positions on the use of that data as evidence.
At the same time, in some European countries, amendments have been passed or planned that open up the possibility of using state 'spyware' tools for lawful targeted surveillance, thus changing the context. Although courts express concerns about the legality of evidence, legislators are moving in the direction of stronger police powers.
In Montenegro, which has been revealing for years that the Sky app is a kind of black box of organized crime, containing traces of agreements on liquidations, cocaine smuggling and money laundering, as well as messages that reveal the connection of clans with individual police officers, civil servants and politicians, the Court of Appeal has taken the position that Sky is digital evidence. The most significant prosecutorial and judicial proceedings were initiated precisely thanks to the material provided to Montenegrin investigators by Europol...
Case law
The French Court of Cassation (Supreme Court) ruled a few days ago in the case of a German citizen who was essentially appealing the legality of the evidence obtained and used against him before German courts.
Member of the Joint Defense Team Bojana Franović Kovačević She told "Vijesti" that the defendant, bearing in mind that he did not have the opportunity to examine the legality of the obtained data before German courts, that the investigation was conducted in France, and that the evidence related to the Sky materials was collected precisely as part of that investigation in France, believed that he had the right to challenge them precisely before a French court.
“As the French Court of Appeal dismissed his appeal as inadmissible because the investigation in France itself did not concern him at all, and therefore he did not have the right to use any effective legal remedy before a national court in France, the French Court of Cassation decided to refer the case to the Court of Justice in Luxembourg. In other words, this legal remedy is accepted only for French citizens who were investigated on French territory. That decision raised two key questions that concern all cases brought before various countries in Europe regarding the Sky materials - whether Article 14 paragraph 1 of Directive 2014/41/EU in conjunction with Article 47 of the Charter of Fundamental Rights of the European Union requires that the executing country provide a legal remedy to the person to verify the legality of the evidence provided through the European Investigation Order, and whether the principle of equal remedies established in the Directive means that a person accused abroad on the basis of such evidence should have the same opportunities in France as a person in domestic proceedings despite all existing obstacles”, stated Franović Kovačević.
She pointed out that this is not the first decision by France to problematize the method of collecting and submitting evidence in international investigations:
“In June of this year, the French Court of Cassation issued another decision, which was not related to the Sky materials, but to the provision of such evidence to other countries, more precisely Spain. In that decision, the French court determined that if the country from whose territory the evidence is being collected must be informed of such an operation and must give its consent to it in order for the evidence to be legally admissible, and in that procedure such notification did exist. However, when it comes to Sky, it is a well-known fact that no country outside the joint investigation team was informed or gave its consent and had the possibility of judicial control over the collection of such materials, which is why the case was referred to the Court of Justice. This decision will also affect our procedures due to the simple fact that in such matters, the position that the principle of international trust applies in this specific case can no longer be defended. This principle is not applicable if the person affected by such a procedure does not have the right in the country of collection to challenge the validity and legality of the collected material, and as we see from this decision, such a legal remedy is reserved only for French citizens. Simply put, in France you cannot complain because you are not French, and in Montenegro they do not allow you to complain because we trust the French. This reasoning leaves you completely without legal protection and it is not acceptable from the point of view of national law or international law”.
Commenting on the decision of the Swiss Court of Appeal, made in August, she said that it best demonstrates how important the above issues are.
This decision determined that evidence obtained in violation of the principle of territoriality was absolutely unusable, that it was a measure of secret surveillance and that the defense must have access to all the material obtained.
"Given that this is undoubtedly a measure of secret surveillance, the question arose whether the results could be used in Switzerland. The conclusion is that this can be assessed solely on the basis of Swiss law, regardless of the fact that the materials were submitted through international legal assistance. The same obligation to assess evidence in accordance with national legislation also exists in our country and in accordance with the provisions of the Law on International Legal Assistance in Criminal Matters. The Zurich decision stated, among other things, that given the fact that there was absolutely no specific suspicion in relation to a specific defendant for a specific criminal offense, Switzerland would never comply with France's request to implement a MITM measure (hacking servers using the Man In The Middle method) because it would not meet the prerequisites under national legislation. There are decisions of Montenegrin courts that reject, for example, the prosecutor's request to obtain complete traffic from base stations in Montenegro for precisely these reasons, however, somehow we have forgotten about our national law in the meantime, which actually resolves the situations in question very easily and simply."
He also points out that it is particularly worrying "the indisputable fact that the Swiss court determined that the data in the case files of the specific case, which are in the Excel spreadsheet, do not correspond to the data in their original form, and that a selection was made regarding the content of the communications and that the messages were subsequently placed in Excel format."
"For all these reasons, all communications that were submitted to Switzerland through international legal assistance were removed from the file. This is precisely what we are highlighting before the national courts in Montenegro, but the courts still do not want to enter into a discussion on this issue and obtain from the prosecution all the necessary information in order to truly discuss important and highly contentious issues, and this is something that will create a huge problem for the Montenegrin judiciary in the long term, because as we see, sooner or later all important arguments must be discussed, either by decision of the domestic court or under duress when ordered to do so by international courts."
Asked how the Joint Defense Team, in light of the different decisions, sees the recent conviction before the court in Berlin, issued against the Belgrade citizen Nikola Vušević, his defense attorney in that case Christian Lodden He said that it was not explained to them on the basis of which his client was identified as an alleged user of Skaja.
"The court was not at all interested in the origin of the aforementioned conversations, nor did the German investigator explain on what basis my client was identified as an alleged Sky user. They received all the data from Europol, although it was not at all possible to determine who at Europol obtained this data and who forwarded it to Germany. However, a German investigator from Europol testified before the court that Serbian investigators also had access to the sku ecc data at Europol. This case is an excellent example of why the recent decision of the French Court of Cassation (16. 9. 2025) is so important: The person concerned by such a measure must be able to defend himself effectively and efficiently against such accusations. It must be clear who had access to the data, when, where, how and why, and who did or could have changed the data," said Lodden.
Franović Kovačević adds that, when all the various decisions are taken into account, and brought into connection with the judgment of the Court of Justice from April 2024, as well as the Yalçınkaya v. Turkey judgment of the Strasbourg Court, "it is clear that we have a serious and real dilemma on how to proceed in these proceedings."
"If France, from which all this started, can stop and ask how to proceed, it is clear that Montenegro must do the same urgently. We have too many important cases in which it is important to establish the truth, but the way things have been done so far, it will not be possible to continue. The Court of Appeal of Montenegro must still appreciate the legal argumentation and I think it is not wise to hide behind the formulation 'this is an electronic document and the principle of international trust applies', because it is clear that this position has been abandoned, first and foremost, by France itself, which we 'trust'. It is clear that all other important international courts have long since abandoned that position and have really tackled all the arguments of both the defense and the prosecution."
Dissonant tones
When asked by "Vijesti" to comment on the decisions in neighboring Serbia, including the one a few days ago that convicted the SBPOK inspector in the Court of Appeal in Belgrade, To Božidar Stolić and his associate Filip Golubović The sentence was confirmed and the Sky application was practically recognized as valid evidence in criminal proceedings in that country. Franović Kovačević also cited the court's ruling of July 23, 2025, which overturned the decision to confirm the indictment:
"Dissonant tones are also coming to us from neighboring countries, so the Court of Appeals of Serbia has issued a decision in which it refers to the principle of international trust, which our court seems to be copying for now, and the same court has issued a decision in another case in which it states that the fact that some evidence was obtained through international legal assistance is not a guarantee of its legality. So, I repeat, the dilemma is serious and real, the procedures are too important to rush through and turn a blind eye to all that is happening in the world and in our country. I hope that they will have the strength, knowledge and capacity to ultimately determine what is acceptable for our legal system and what is not, as well as to overcome the really complicated norms of various jurisdictions that are certainly a factor in this specific case, as well as the norms of international law regarding international investigations and obtaining electronic evidence, and that we will have the strength and integrity to apply our laws that are in line with all international standards."
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