European and Irish law on mobile phone and computer forensics has moved sharply in favour of strict proportionality, data‑minimisation and clear judicial oversight, which creates real opportunities for defence solicitors and barristers to challenge overbroad or poorly governed digital evidence. Used properly, these developments let the defence attack admissibility, scope and disclosure around phone and computer extractions, and argue for exclusion or weight‑reduction where police have treated a device as an “open season” dataset rather than a tightly targeted source of evidence.eucrim+2

​

Key European principles defence can weaponise

Across the European Court of Human Rights (ECtHR) and Court of Justice of the EU (CJEU), mobile phone and device searches are now clearly recognised as serious interferences with private life and data‑protection rights, demanding strong safeguards. Guidance stresses the right to privacy (ECHR Article 8), fair trial (Article 6) and data‑protection duties such as data minimisation, purpose limitation and necessity when handling electronic evidence.osce+2​

A recent Grand Chamber judgment of the CJEU on police access to mobile phone contents under Directive 2016/680 confirms that full, uncontrolled access to an entire phone is so intrusive that it must be strictly regulated. The Court emphasised: prior review by a court or independent authority, strict proportionality, clear definition of the categories of data and offences justifying access, and effective information rights for the data subject.eucrim​

How Irish defence teams can use this

• Argue that warrants or statutory authorisations permitting “all data” extraction from a phone or computer, without specifying categories or time frames, breach EU data‑minimisation and proportionality requirements and therefore infringe Charter and ECHR rights.osce+1​
• Challenge investigations where the client was never properly informed of the nature or extent of digital exploitation of their device, invoking EU law requirements to inform data subjects of access attempts unless this genuinely prejudices the investigation.eucrim+1​

European case law defence angles

Recent European litigation has highlighted that blanket or routine extractions from phones, particularly without good reason or proper legal basis, can violate human rights and data‑protection rules. For example, national courts have criticised practices of extracting “every mobile phone seized” or compelling PINs from migrants and other vulnerable groups as unnecessary and disproportionate, leading to findings of unlawfulness and violations of privacy rights.article19+1​

The OSCE’s guidance on cybercrime investigations and electronic evidence distils ECtHR and CJEU jurisprudence into practical safeguards: clear legal basis, targeted rather than indiscriminate searches, judicial supervision, and the risk of inadmissibility where safeguards are ignored. For defence, this material supports motions contending that over‑broad extractions and fishing expeditions through years of chat, photos and cloud data lack a sufficient legal and factual foundation.osce​

Arguments to raise

• Any device search that is not clearly linked to defined offences, time windows and data types can be attacked as a disproportionate trawl contrary to ECHR Article 8 and EU data‑protection standards.journals.sagepub+1​
• Where extraction policies default to “full image of the device and all linked cloud accounts,” defence can argue that the system itself is structurally disproportionate and that only narrowly relevant slices should be admitted or relied upon.eucrim+1​

New EU e‑evidence framework and safeguards

The emerging EU framework on cross‑border electronic evidence, including Regulation (EU) 2023/1543, has been criticised by fair‑trial NGOs for weak defence safeguards and insufficient judicial control over remote data orders. However, those same critiques and commentaries are powerful tools for defence submissions, showing that without strong safeguards, e‑evidence risks undermining equality of arms and adversarial testing.fairtrials+1​

Analyses of the Regulation stress the need for robust notification, challenge and review mechanisms when electronic data from service providers is obtained and transmitted across borders. Irish defence lawyers can use these materials to demand disclosure of the exact process, orders and legal basis used to secure cloud data, and to argue that any failure to comply with those safeguards should weigh against admissibility or reliability.fairtrials+1​

Practical defence uses

• Seek detailed disclosure on all EU production orders, preservation requests and mutual‑assistance channels used to obtain phone backups, cloud accounts or messaging logs.fairtrials+1​
• Argue that opaque or ex parte cross‑border requests that bypass meaningful defence oversight offend fair‑trial guarantees under ECHR Article 6 and the Charter.europeanlawinstitute+1​

Ireland: digital evidence pressure points for defence

The Irish criminal justice system has acknowledged that smartphones and digital evidence are now “game‑changers” in prosecutions, prompting legislative reactions such as the Communications (Retention of Data) (Amendment) Act 2022 after CJEU rulings in cases like Dwyer v Commissioner of An Garda Síochána on indiscriminate data retention. Irish commentary also notes the relentless growth in digital evidence volumes and the resulting pressure on courts and disclosure, which can be leveraged by defence to argue that unmanaged volume increases the risk of missed exculpatory material and flawed selection.lawsociety+1​

In Director of Public Prosecutions v W.I. ( IECA 148), the Court of Appeal dealt with discrepancies between Garda phone extraction and a later, more complete defence‑commissioned extraction using updated forensic tools. While the court accepted there was no deliberate withholding and upheld the conviction, it recognised that fresh digital evidence from more advanced tools can be material and must be evaluated under established fresh‑evidence tests.casemine+1​

How Irish barristers/solicitors can deploy these developments

• Challenge retention and access: Link any broad retention or historical location analysis of mobile data to EU case law on unlawful indiscriminate retention, arguing for exclusion or weight reduction where the statutory basis has been strained.lawsociety+1​
• Use independent extractions: Commission defence‑side re‑extraction of phones and computers using current forensic tools to identify missing, mis‑parsed or context‑altered artefacts, then rely on DPP v W.I. to argue that such fresh digital evidence should be admitted where it is credible, material and could have influenced the verdict.vlex+1​
• Attack “all‑data” warrants: Rely on the CJEU Grand Chamber ruling on mobile phone access to argue that Irish warrants or statutory powers authorising undifferentiated imaging of phones and laptops, without specifying data types and timeframes, breach EU law and should be read down or evidence excluded.osce+1​

Concrete courtroom strategies for the defence in Ireland

1. Pre‑trial motions on admissibility and scope
   • Seek disclosure of extraction logs, tools, versions, hash values and filter criteria for all mobile and computer searches.casemine+1​
   • Argue that evidence obtained through legally defective or disproportionate access (no prior independent authorisation, no data‑minimisation, no proper information to the accused) violates EU standards and should be excluded or given little weight.journals.sagepub+1​
2. Equality of arms and disclosure arguments
   • Use OSCE and Fair Trials analyses to support submissions that complex e‑evidence requires full defence access to raw data, not just prosecution‑curated exports or screenshots, to maintain equality of arms.fairtrials+1​
   • Where disclosure is partial or excessively delayed due to volume, argue that the accused has not had “adequate time and facilities” to prepare a defence, engaging ECHR Article 6.osce​
3. Narrative reframing for judges and juries
   • Emphasise that phones and computers contain huge quantities of sensitive, irrelevant data, so proper policing should be surgical, not total – and that over‑collection increases the risk of confirmation bias and misinterpretation.journals.sagepub+1​
   • Present independent forensic timelines from the defence expert that highlight gaps, alternative explanations, missing logs or selective harvesting in the State’s digital narrative.irishexaminer+1​

Used together, these European and Irish developments let defence solicitors and barristers turn the technical and legal complexity of mobile and computer forensics into a strategic advantage, forcing the State to justify every step of its digital evidence handling and creating real opportunities for exclusion, alternative timelines and reasonable doubt.casemine+1​

1. https://eucrim.eu/news/ecj-ruled-on-police-access-to-mobile-phone-data/
2. https://www.osce.org/files/f/documents/e/3/554901.pdf
3. https://journals.sagepub.com/doi/10.1177/20322844251393147
4. https://www.europeanlawinstitute.eu/fileadmin/user_upload/p_eli/Publications/ELI_Proposal_for_a_Directive_on_Mutual_Admissibility_of_Evidence_and_Electronic_Evidence_in_Criminal_Proceedings_in_the_EU.pdf
5. https://www.article19.org/wp-content/uploads/2023/08/Nabrdalik-v-Poland-Amicus-August-2023.pdf
6. https://www.fairtrials.org/articles/legal-analysis/the-achilles-heel-of-e-evidence-regulation-eu-2023-1543/
7. https://www.fairtrials.org/articles/news/fair-trials-europe-raises-concerns-on-the-roadmap-for-lawful-and-effective-access-to-data-for-law-enforcement/
8. https://www.lawsociety.ie/gazette/top-stories/2023/november/smartphones-game-changer-in-criminal-cases–dpp/
9. https://www.irishexaminer.com/news/courtandcrime/arid-41718702.html
10. https://www.casemine.com/judgement/uk/648a1714d72ae126cdaa0e1e
11. https://ie.vlex.com/vid/director-of-public-prosecutions-935190341
12. https://hudoc.echr.coe.int/eng?i=001-235129
13. https://curia.europa.eu/juris/document/document.jsf?text=&docid=285363&pageIndex=0&doclang=EN&mode=lst&dir=&occ=first&part=1
14. https://www.europeanrights.eu/public/sentenze/Ireland_24.03.2023_2023IECA70.pdf
15. https://www.schoenherr.eu/content/seizure-and-examination-of-mobile-data-and-data-carriers-in-austria-where-do-we-stand-and-what-s-next
16. http://privacyinternational.org/legal-action/nabrdalik-v-poland
17. https://www.taylorwessing.com/en/insights-and-events/insights/2020/08/court-of-appeal-gives-guidance-on-digital-records-held-on-electronic-devices-in-criminal-proceedings
18. https://hudoc.echr.coe.int/eng?i=002-14395
19. https://www.rte.ie/news/2023/1012/1410509-celebrity-court/
20. https://cedpo.eu/data-protection-weekly-21-2024/