We are in front of the most polemic measure of investigation. The entrance into a domicile, the interception of written correspondence, the interception of telephonic communications, are measures which may be expected by those who commit a crime. But who would think that a camera is recording what is happening at its home? Are the criminals aware that their conversations into a cell may be recorded? 
Until the year 2015 the Spanish Penal Procedural Law (in Spanish Ley de Enjuiciamiento Criminal, henceforth LECrim) didn’t mention anything regarding the possibility to be spied by the State at your home, office or car. And despite this silence the Spanish jurisprudence admitted the legality of these interferences in the intimacy of the Spanish citizens by making a broader interpretation of the law than was really the proper. Until the reform of the LECrim by the Organic Law 13/2015 (in Spain a Organic Law is a law that regulates fundamental rights, which are those established from the article 14 to article 29 of the Spanish Constitution), the Spanish tribunals fitted the reception and recording of conversations into the old article 579.2 LECrim which regulated the interception of the telephonic communications. This biased interpretation was clearly against the law, chiefly because it didn’t comply with the principle of reserve of law recognized in the art. 53.1 of the Spanish Constitution (henceforth CE), such principle obliges the legislator to regulate all the fundamental rights recognized in the CE in a norm with the rank of law, furthermore it has to be a Organic Law (art. 81.1 CE) as consequence of the sort of rights developed. Who solved this anomalous situation was the Spanish Constitutional Tribunal, in its famous sentence nº 145/2014, it declared that the reception and recording of conversations was ilegal because it was not expressly contemplated in the LECrim, it said that is was not a matter of a vaguely regulated measure in the law, the problem was that the LECrim didn’t talk about such measure in any part, therefore those who would be subjected to that measure could not foresee it. Finally, as I have hinted, the LO 13/2015 introduced in the LECrim a chapter which had as object to regulate expressly and as detailed as possible this measure of investigation, concretely it is regulated from the art. 588 quater a. to the art. 588 quater e. of the LECrim.
The interception of conversations moves in a plane of ambiguity if we regard the right which is affected by this measure. Usually you will find in the Spanish jurisprudence that the right which suffers when this measure is applied, is the right to the secret of the communications (art. 18.3 CE), but this is not entirely true, because the right to the secret of the communications protects the means through which the communication is taking place, and in a conversation between two or more persons talking in the same place the means could only be the air, which is not precisely to what the right to the secret of the communications was developed, at the beginning it was thought to protect the letters and after to protect a phone call. Thereby it doesn’t fit completely in the right to the secret to the communications, and in the right to the intimacy? the right to the intimacy (art. 18.1 CE) has a broader use, for instance since the right to the secret of the communications only protect a communication in process, once a letter is open and put in a safe place it is protected by the right to the intimacy. But the right to the intimacy is softer, weaker, doesn’t have a especial provision in the CE asking for a judicial resolution, in short we cannot protect a conversation only with the right to the intimacy, so even when we know that the right to the secret of the communications is not correct, it is the right used by the Spanish tribunals when the have to link this measure with a fundamental right. Another right affected by this measure of investigation would be the right to the inviolability of the domicile (art. 18.2 CE), it would happen, as later we will see, when the investigation of the suspect is carried out in a domicile. And indirectly the interception of a conversation may affect a right as important as the right to the defence (art. 24.2 CE), imagine two suspects being driven to prison in the same van, they may talk about who commit the crime, or about their strategy of defence, when the art. 24.2 CE recognized the right to not confess yourself guilty and to not declare against yourself. This last example is now allowed by the Spanish tribunals because, according to them a spontaneous declaration which has not been provoked by the police is not protected by the right to not declare. Furthermore, the art. 118.4 LECrim admits the possibility that the conversation of a suspect with its lawyer may be listened by the police if ethere are evidences of a crime committed by the lawyer.
Let´s move on. It is impossible not to have the temptation to compare the regulation of the interception of the telephonic communications to the reception and recording of conversations. If we don’t think with calm we rapidly believe that since the right affected are the same, the right to the secret of the communications, the norms which regulate them should be the same too, but no. The reception and record of conversations has a deeper impact into the right to the intimacy of the subject investigated, when we intercept a telephonic conversation we are only allowed to know the content of such communication, our knowledge of the subject will stop there. On the contrary when a judge authorizes the reception and record of conversations our knowledge of the subject investigated will comprehend all what is said in the ambit of the measure approved, of course we also will listen phone calls (only the side of the subject investigated), but also besides all that the microphones and cameras installed can listen and see, this is way this measure is much more aggressive than the simple interception of the telephone. When a judge authorizes the interception of a telephone it will listen all that is said through the line of the telephone intervened, furthermore the judge may authorize the intervention of telephones which are not owned by the subject investigated under certain conditions (art. 588 ter c), the only limit will be temporal (art. 588 ter g.), on the contrary, when a judge authorizes the reception and recording of a conversation, the authorization will cover only a concrete meeting or concrete meetings, and the temporal limit of the measure will be the duration of that meeting or meetings authorized under the judicial authorization, here is where we see clearly how different are both measures, and how is more affected the right to the intimacy of the subject investigated with the reception and recording of the conversations.
If we use a telephone number to restrict the ambit of the intervention of a telephone, we have said above that to limit the ambit of the intervention of a conversation we use a meeting or meetings. How do we delimit this meeting or meetings? According to the Spanish Public Accusation´s (in Spanish Fiscal, henceforth Fiscal) instructions, we have to take into account three requisites 1) a concrete place, 2) the persons who will assist to the meeting (always has to assist the investigated) and 3)  a temporal delimitation. Let see one by one these three requisites. 1) A concrete place: the art. 588 quater a. doesn’t limit the possible options when the police has to choose a place where to install the devices to listen and/or see, it may choose a public place, a closed place, or even a domicile. In the latter is where the police has to be more cautious, the Spanish jurisprudence has declared that the police cannot use devices to see what is happening inside a domicile without a judicial resolution authorizing it. The place chosen may be a restaurant, a garage, a car, but only when the place chosen is a domicile the right to the inviolability of the domicile will be affected, therefore is when the judicial resolution has to be as motivated as possible, it has to be specially scrupulous when analyzes that the measure comply with the principle of proportionality, because we have not say anything yet, but of course that the principles of the articles 588 bis apply too to this measure. 2) The persons who will assist to the meeting: the most important will be always the proper investigated, is him who motivates the measure, the others may be identified only by their name, or nickname. The concretion of the investigated is key, because the measure can be only approved in relation to one person, on the contrary, in the interception of the telephone is allowed the intervention of phone numbers owned by third persons (art. 588 ter c). And 3) A temporal delimitation: it is necessary to specify the moment when the meeting or the temporal space where the meeting will take place. This last requisite is important because during the interception of the conversations is not allowed to approve extensions of the measure, when the meeting or meetings authorized have ended, it has to be another judicial resolution which authorizes another new intervention.
The judicial resolution which authorizes the intervention of the conversations deserves a special mention. The requisites stablished to authorize the reception and recording of conversations are clear in the law, articles 588 quater b and article 588 quater c. so the judge has to motivate the judicial resolution according to the fulfillment of these requisites, nonetheless they are not the only that the judge have to take into consideration. As the Spanish jurisprudence has stated, the investigation of a crime which fits in the art. 588 quater b.2.a)1º, doesn’t serve on its own to give sense to a judicial resolution approving the installation of cameras and microphones in a domicile. As we have said above, the principle of proportionality (art. 588 bis a LECrim) has to be scrupulously complied in this case, therefore the judicial resolution has not to be scarce in motives which justify the measure, and even more if it not only authorizes the intervention of the conversations but also the reception of images concerning the domicile of the subject investigated. For the sake of clarification all what have been said until now, the measure of investigation may consist of reception and recording of only sound, both sound and image, or only image, though in this last case there is a proper article in the LECrim which regulates this measure, the art. 588 quinquies a, it is only applicable to the reception and recording of image not sound, and only in public places, thereby the reception and recording of only images inside a home will always require a judicial resolution authorizing it.
We can sum up everything we have seen in one phrase, be careful with what you say or do wherever you are, because the State may be watching and listening to you and will use it to put you in jail.