隨著雲端運算技術的飛速發展，個人資訊儲存態樣已由物理實體裝置移轉至雲端空間。此外，使用者於各項雲端服務留存之數位足跡，亦足以勾勒其完整生活樣貌，此等詳盡資料遂成為偵查機關重要之取證目標。在數位證據快速增加的時代下，我國現行刑事訴訟法規範能否周延保障人民日益重視之資訊隱私權，即為本文之探究核心。 首先，本文藉由梳理美國聯邦憲法增修條文第 4 條之演進、分析美國法院實務案例與現行法制，剖析美國法如何應對雲端資料之取得，供我國未來法制借鏡。其中，美國法中「第三人原則」乃雲端資料取得之爭點核心，即個人若將資訊自願揭露予第三方業者，即應承擔遭揭露之風險，而難以主張合理隱私期待。聯邦最高法院於 Carpenter v. United States 案中開始限縮該原則之適用範疇，從「資訊之本質」角度思考，重新建構個人對於數位資訊之合理隱私期待。 本文旨在借鏡美國法制之演進與嬗變，針對我國未來雲端資料取得與扣押之規範提出立法芻議，期能於刑事偵查利益與保護人民資訊隱私權間取得平衡。;As cloud computing advances， personal data storage has shifted from physical devices to the cloud. The extensive digital footprints left on these platforms can now map a user′s entire private life， making them prime targets for criminal investigations. This thesis examines whether Taiwan′s Code of Criminal Procedure adequately protects information privacy in this era of growing digital evidence. To address this， the thesis first examines the evolution of the Fourth Amendment to the U.S. Constitution and scrutinizes U.S. jurisprudence to understand how the American legal system regulates cloud data acquisition， thereby providing a comparative reference for Taiwan’s future legal reforms. A pivotal controversy in U.S. law regarding cloud data is the "Third-Party Doctrine，" which posits that individuals who voluntarily disclose information to third-party providers assume the risk of exposure and thus forfeit their "reasonable expectation of privacy." However， in the landmark case Carpenter v. United States， the U.S. Supreme Court began to constrain the application of this doctrine. By re-evaluating the "nature of information，" the Court sought to reconstruct the standard for a reasonable expectation of privacy in the digital age. Drawing on these U.S. developments， this thesis proposes legislative recommendations for the acquisition and seizure of cloud data in Taiwan， aiming to strike a balance between the needs of criminal investigation and the protection of personal information privacy.
