SIS II alerts are checked by filing a data-access request with your national SIRENE bureau under EU Regulation 2018/1862. The bureau confirms whether any alert — European Arrest Warrant, discreet surveillance, or refused-entry flag — exists in your name. No online tool can query SIS II; the request must be filed through the correct national channel, typically through counsel.
The Schengen Information System (SIS II) is the largest shared database for border and police cooperation in Europe. It holds alerts circulated among the 29 Schengen-associated states, including European Arrest Warrants, discreet surveillance flags, refused-entry bans, and missing-person alerts. Unlike Interpol's database, SIS II is governed by EU law and has its own data-protection framework. Your right of access is exercised through your national SIRENE bureau — the operational unit in each Schengen state that manages SIS II data.
The Three Categories of SIS II Alert
SIS II alerts fall into several categories, each with different operational consequences. Understanding which category applies to you is essential, because the legal response differs.
Category A alerts are European Arrest Warrants — judicial decisions requiring the location, arrest, and surrender of a person for prosecution or sentence execution. A Category A alert triggers immediate detention at any Schengen external border. These are the most operationally severe alerts, because they are backed by a judicial warrant and executed automatically.
Category B alerts are discreet surveillance or specific-check flags. They do not require arrest but instruct border authorities to conduct enhanced scrutiny — longer questioning, secondary inspection, or reporting the person's location to the issuing state. A Category B alert can cause significant delays and may escalate to detention if the officer identifies grounds. These alerts are often used in early-stage investigations.
Refused-entry flags prevent a non-EU national from entering the Schengen area. They can be issued on grounds of public security, public health, or immigration violations. A refused-entry flag is distinct from a criminal alert — it does not lead to arrest, but it prevents entry and can cause detention pending return.
Critical Warning for Travelers
A SIS II alert can exist independently of any Interpol notice. A clean CCF response does not mean a clean SIS II check. If you travel to or through the Schengen area, query SIS II through SIRENE in addition to querying Interpol through the CCF.
How to File a SIRENE Data-Access Request
The right of access to SIS II data is recognised under EU Regulation 2018/1862. The request is filed with your national SIRENE bureau — the unit that manages SIS II data in your country of nationality or residence. The bureau must respond within a reasonable period, confirming whether any alert exists and, if so, disclosing its nature and issuing state.
- Identify the correct SIRENE bureau: Each Schengen state has one SIRENE bureau. If you are a national or resident of a Schengen state, file with your country's bureau. If you are not, counsel identifies the most appropriate bureau based on your travel pattern.
- Submit a written access request: The request cites EU Regulation 2018/1862 and asks the bureau to confirm whether any alert — arrest, surveillance, or refused-entry — exists in your name. Identity documents are required.
- Receive the bureau's response: The SIRENE bureau responds in writing. If an alert exists, the disclosure identifies the issuing state, the category, and the underlying basis. If no alert exists, the response functions as a clean confirmation.
Challenging an Erroneous SIS II Alert
If the SIRENE response reveals an alert that is erroneous, outdated, or non-compliant with EU law, a correction request can be filed with the issuing state's SIRENE bureau. The request must document why the alert should be withdrawn — for example, that the underlying case has been resolved, that the alert is based on a politically motivated prosecution, or that the data is factually incorrect. The issuing bureau is obliged to review the request and respond.
Where the issuing state refuses to withdraw the alert, a legal challenge can be filed in national courts under the data-protection framework. EU law also provides for a complaint to the European Data Protection Supervisor, although this route is slower. In practice, the most effective approach is a combined strategy: a correction request to the SIRENE bureau, a CCF deletion petition if the alert also exists in Interpol, and a national court challenge if the SIRENE bureau refuses to act.
In one case, a client's SIRENE response revealed a Category A alert based on an EAW issued by a Baltic state. The underlying prosecution had been dismissed locally, but the EAW had not been withdrawn. Counsel obtained confirmation of the dismissal from the issuing court, filed a correction request with the issuing SIRENE bureau, and the alert was removed within four weeks. A parallel CCF request confirmed that the matter had also been circulated as an Interpol diffusion, which was separately deleted.
What to Do in Practice: Secure Your Clearance
SIS II is a separate system from Interpol, and a clean check in one does not guarantee a clean check in the other. If you travel to or through the Schengen area, query SIS II through SIRENE alongside your CCF request. The two queries together cover the databases that Schengen border terminals query in real time.
If you suspect your name is on an international watchlist or have an upcoming flight, do not leave your freedom to chance at a passport terminal. A confidential Interpol lookup or a comprehensive Pre-Travel Legal Check filed through Swiss legal counsel secures absolute clarity within days. Contact our Basel office confidentially to secure your legal travel shield.