為了讓民眾回歸社會生活，德國聯邦近期提出3G規則（3G-Regel）作為民眾個人進入室內空間之條件，讓已接種疫苗者（Geimpft）、染疫已痊癒者（Genesen）與接受檢測且陰性結果者（Getestet）出示有效證明後，得以免戴口罩不受限的出入特定公共場所、參與文化或休閒活動。其中，又以接種疫苗更為行動自由權不受限的關鍵。而在部分的邦，則採用更嚴格之2G規則（2G-Regel），只有接種過疫苗或染疫後痊癒之國民，才能不受出入行動的限制，連持有24小時內PCR檢測陰性結果證明，亦不得進入室內空間。在德國，民眾並無接種新冠疫苗的法定義務，儘管接種新冠疫苗是目前控制疫情擴散之最佳策略，但不論是採用3G、2G或2G+規則，在無法律作為強制要求接種的法源依據下，若以疫苗接種、染疫痊癒作為自由出入的要件，則必然有國家過度介入個人基本權利的疑慮，因此有必要在比例原則理論之檢視架構下，檢驗3G及2G規則之合憲性。

The Federal Republic of Germany and state governments enacted 3G-Regel as a requirement for everyone entering indoor spaces in 2021 so that the general public could resume their current social life as quickly as possible. Allowing those who have been vaccinated (Geimpft), those who have recovered from COVID-19 (Genesen), and those who have been tested with a negative result (Getestet) to enter and exit public spaces and participate in cultural or recreational activities without wearing a mask upon presenting valid proof. Particularly, vaccination is crucial to the unrestricted right to freedom of movement. Some states have adopted the stricter 2G-Regel, which exempts from entry and exit restrictions only citizens who have received the COVID-19 vaccination or who have recovered from COVID-19. Even if they have proof of a negative result from a PCR test taken within 24 hours, they are prohibited from entering indoor spaces. In Germany, there is no legal requirement for COVID-19 vaccination, despite the fact that vaccination is currently the most effective method for preventing the spread of COVID-19. Regardless of whether 3G-Regel, 2G-Regel, or 2G+-Regel are in effect, COVID-19 vaccination without the relevant laws such as the Communicable Disease Control Act as the legal basis for mandatory vaccination, and using vaccination and recovery from COVID-19 as requirements for freely entering and exiting places will raise questions about excessive state interference with the fundamental rights of individuals. Therefore, it is necessary to examine the constitutionality of the 3G-Regel and 2G-Regel under the inspection architecture of the principle of proportionality.