INSIGHTS
A practical account of how criminal mutual legal assistance requests to Türkiye are routed and executed, including special procedures, search and seizure, video links, provisional measures and transfer of proceedings.
What determines whether a request produces usable material, and why most of it is settled before the request is sent.
Law stated as at 1 August 2026. There is no official English translation of Law No. 6706; translations are the author’s own and the Turkish text governs.
Three layers apply to a mutual legal assistance request involving Türkiye, and they apply in this order.
Treaties first.Law No. 6706 expressly preserves the international agreements on judicial cooperation to which Türkiye is a party, along with other statutory provisions. Where an instrument is in force between the requesting state and Türkiye, it governs, and it may provide for procedures, channels and time limits different from those described below.
The principal instrument is the European Convention on Mutual Assistance in Criminal Matters (ETS 030). Türkiye signed it on 23 October 1959, ratified it on 24 June 1969, and it entered into force for Türkiye on 22 September 1969. Türkiye is also a party to the Second Additional Protocol to that Convention (CETS 182), which matters for the reasons set out in section 9.
Then Law No. 6706, which supplies the domestic framework, including where there is no treaty.
Then the Code of Criminal Procedure, which applies to matters the Law does not address.
Türkiye being a party is only half of the question. Several of the tools that matter in practice — hearing by video link, direct contact between judicial authorities, joint investigation arrangements — are available only where both states are bound by the same instrument. The first task in any matter is therefore to establish what the requesting state has ratified, not only what Türkiye has. Assuming an instrument is available and drafting around it is the most expensive error in this area, since the assumption usually surfaces only after the request has been sent.
Where there is no treaty, cooperation proceeds on the basis of reciprocity, and execution may be made conditional on the requesting state guaranteeing that it will meet equivalent Turkish requests.
The directions should be kept separate. Sections 2 to 9 below concern a request made to Türkiye (Turkey) and executed here. Section 10 identifies two rules concerning a Turkish request carried out abroad and information sent by Türkiye without a request. Section 11 concerns transfer of an investigation or prosecution, which is not simply another evidence request.
Requests do not pass directly between courts unless an instrument in force provides for it.
The Ministry of Justice acts as Central Authority. It decides whether an incoming request is accepted, what form of cooperation applies and what method is followed. It may consent to, limit, or attach conditions and guarantees to the use of the information and documents sought. Conditions the Central Authority accepts are binding on the Turkish judicial authorities that carry out the request.
Two discretionary filters sit at this stage and both are worth knowing before drafting.
The Central Authority may decline a request where there is a clear disproportion between the seriousness of the offence and the effort, time and expense of executing it, or where the request concerns steps a state habitually declines to take. A wide-ranging request on a minor matter is at risk here in a way that a narrow request on the same matter is not.
And it may take the opinion of relevant public bodies before deciding. Requests that touch regulated sectors can therefore take longer than their apparent complexity suggests.
Assistance may be refused where:
Execution would prejudice Türkiye’s sovereign rights, national security, public order or other fundamental interests;
The conduct is a purely military offence, an offence of thought, a political offence or one connected with a political offence;
There are credible reasons to believe that the person concerned will be subjected to investigation, prosecution or punishment on account of race, ethnicity, religion, nationality, membership of a particular social group or political opinion, or will be exposed to torture or ill-treatment; or
Basic guarantees of the rights of the defence are absent in the requesting state.
A separate ground applies to the act itself. Where a Turkish court has already convicted or acquitted the person of the same act, or the offence has been amnestied or is time-barred, assistance in respect of that act may be declined.
Requests are executed in accordance with Turkish law. But where the requesting authority asks for a particular procedure to be followed, that request will be accommodated provided it is not contrary to Turkish law.
This is one of the most useful provisions in the Law for foreign counsel where the form of the resulting material matters in the receiving forum.
Material gathered abroad frequently fails not because it was unlawfully obtained but because it was obtained in a form the receiving forum cannot use: a statement not taken on oath in the required manner, an exhibit without a continuous record of handling, an interview conducted without a caution in the terms the trial court expects. Turkish authorities will follow a specified procedure where they can. They cannot follow one that was never specified.
The special procedure must be requested. If it is omitted from the original request, the practical route is ordinarily a supplementary or replacement request. The Law does not say that a later request is legally impossible, but routing it through the same authorities introduces avoidable bureaucratic delay.
Turkish authorities may also refuse a request in whole or in part, or ask for further information or documents — so an incomplete request is not necessarily fatal, but it is expensive in time.
Foreign authorities may ask to be present when the requested step is carried out. The request is granted where it is considered appropriate, and it is worth making where the manner of execution matters to the receiving forum.
A warning of coercive measures in a service request. Where a request for service of documents contains a warning that restrictive or coercive measures will be applied, the request is refused. Warnings of that kind may appear in standard-form documents in other systems. For a request to Türkiye the warning has to be removed; once the defective request has entered the transmission route, correcting it will ordinarily require redrawing or supplementing the request and sending it through the bureaucracy again.
The threshold for coercive measures. A request for search or seizure is subject to a condition that does not apply to the rest of the regime: the offence must be one for which extradition would be available. Evidence requests that would be granted on a lesser offence will not necessarily support a search or a seizure. Where a request bundles ordinary evidence-gathering with a coercive measure, the coercive limb can fail on the threshold while the rest succeeds, and counsel who have not separated the two will not know which happened.
Where delay would be prejudicial, Turkish authorities may take provisional measures to preserve evidence before the formal incoming request reaches Türkiye.
That route carries a hard limit. If the formal assistance request does not reach the Central Authority within forty days of the provisional measure being taken, the measure is lifted immediately by the competent authority.
Forty days is short once translation, certification and transmission through central authorities are accounted for. The practical consequence is that preparation of the substantive request should begin at the same time as the urgent application, not after it. Counsel who treat the urgent application as the first step and the request as the second will lose the measure.
Where property, immovables, rights or receivables have been seized in Türkiye on a foreign request, Turkish judicial authorities are required to ask the requesting state at least once a year whether the measure is still required.
The statute imposes the annual enquiry duty but does not say that a failure to answer automatically terminates the measure. The practical risk is bureaucratic: the enquiry may be routed to an authority that has reorganised, reassigned or closed the file, leaving the continuing basis of the measure to be questioned or delaying the next decision. Diary management on the requesting side is therefore part of the substantive work rather than an administrative afterthought.
The Turkish-law mechanics of seizure, including what has to be established and how measures end, are set out in MASAK Measures in Türkiye: Suspension, Seizure and Review.
Material provided through assistance may not be used outside the investigation, prosecution or enforcement for which it was requested, unless the sending state consents.
Three situations do not require consent:
The legal characterisation of the offence changes;
New suspects or defendants are brought into the same proceedings after the assistance step; or
The material is needed in civil proceedings connected with the same offence.
Counsel considering whether Turkish material can be deployed in another proceeding should start here, because the restriction attaches to the material rather than to the party holding it. Obtaining consent is a request in its own right and should be anticipated rather than discovered.
Assistance may be sought by way of audio-visual link, and this is one of the places where the treaty layer does real work.
Article 9 of Law No. 6706 is the domestic reflection of the provision on hearing by video conference in the Second Additional Protocol to the Convention (CETS 182), to which Türkiye is a party. The route is therefore open on the Turkish side.
The Law treats the two directions differently, and both are expressly conditioned on a treaty basis.
Where a Turkish authority asks for a hearing to be conducted by video link, the step is carried out under Turkish direction and Turkish law provided an applicable international agreement so provides.
Where a foreign state asks for a hearing in Türkiye by video link, the step is conducted under the direction of the requesting state’s authorities and under that state’s law — again provided an applicable agreement so provides. Turkish authorities are present and ensure that the fundamental principles of Turkish law are not breached. That allocation is worth noting: the evidence is taken under the requesting state’s procedure, which is precisely what makes the route valuable where the material has to be usable in that state’s court.
The condition is the point. Reciprocity alone does not open the video-link route; an applicable international agreement binding both states must provide for it. Where the requesting state has not ratified the Second Additional Protocol, the CETS 182 route is unavailable, but another bilateral or multilateral agreement may supply the necessary basis and must be checked before ordinary examination is treated as the only route.
A Turkish request carried out abroad. Where a foreign state carries out a step requested by a Turkish judicial authority in accordance with that state’s own law, Article 7(1)(ç) treats the step as valid for Turkish purposes. The rule is about the outgoing Turkish request; it should not be extended without analysis to material a foreign state sends on its own initiative.
Information sent by Türkiye without a request. Where Turkish authorities learn, in the course of an investigation or prosecution, of information that could cause another state to open a criminal investigation, Article 7(2) permits them to transmit it through the Central Authority without any request having been made. A file abroad may therefore have originated in Türkiye rather than in the state conducting it, which is worth establishing where the origin of an investigation is in issue.
Where assistance is not enough, the Law provides for the transfer of an investigation or prosecution between states, in both directions, for offences carrying a maximum of at least one year’s imprisonment.
Türkiye may transfer where the suspect or defendant cannot be brought before the Turkish court because they are a national of the other state, or their defence cannot be taken through assistance; or where the person is habitually resident abroad or the evidence is located abroad, such that transfer would better serve the establishment of the facts.
The consequences are structured rather than open-ended. On acceptance of a transfer of investigation, the opening of a public prosecution is deferred; if the foreign authority brings a case, a decision of no grounds for prosecution follows. On acceptance of a transfer of prosecution, proceedings are stayed; if the foreign authority convicts, the Turkish case is discontinued. Where the foreign authority does something else, the reasoning of that decision is assessed and the Turkish proceedings may resume. Türkiye may also resume where the other state withdraws its acceptance or where the transferred proceedings are not being properly conducted.
Türkiye may take over proceedings from abroad, but not where the person is not habitually resident in Türkiye, is not a Turkish national, where the offence was committed outside the requesting state’s territory, or where the person has already been tried in Türkiye for the same act.
Steps and evidence produced under the other state’s law are treated as valid for Turkish purposes.
Costs of executing a request are borne by the executing state unless the central authorities agree otherwise. Budgeting for the Turkish side of an evidence request is therefore usually a translation and coordination question rather than an execution-cost question.
Reading the framework end to end, the decisions that determine the outcome are made before the request is sent:
Which instruments are in force between the requesting state and Türkiye, and what each permits
Whether any coercive measure is sought, and whether the offence meets the extradition threshold for it
What procedural requirements the receiving forum will impose on the material, stated expressly in the request
Whether service documents contain warnings of coercive measures, which must be removed
Whether provisional measures are needed, and whether the substantive request can be completed within forty days
What the material will be used for, and whether that use falls within the purpose for which it was requested
Where assets are to be seized, who on the requesting side will answer the annual enquiry
A request that resolves those seven points before transmission will usually succeed or fail on its merits. A request that does not will usually fail on something else.
This article describes the domestic framework. Where an instrument is in force between the requesting state and Türkiye, that instrument governs and may differ on every point discussed — channels, thresholds, time limits and available measures.
Nothing here addresses what the receiving forum will accept, which is a question for the law of that forum. And execution timetables in practice are affected by translation, workload and the number of authorities a request has to pass through, none of which appears in the Law.
This article describes general procedure and does not constitute legal advice on any particular matter.
This publication is general information and does not constitute legal advice for a specific matter.