本文以基層員警取締性交易的執行過程和結果為例，探討「政策執行」對性交易這樣的爭議型政策的意涵。既有的許多執行研究早已指出，一個沒有社會共識的政策很難「有效執行」，然而絕大多數的政策是不可能等待「社會共識」的。那麼，這些在決策階段沒有被「化解」的政策爭議，到了執行階段，會被執行者如何詮釋？對執行過程造成什麼影響？「執行無效」或「執行不力」的意義是什麼？對於政策標的團體又有什麼影響？此為本文主要發問。 透過對於基層員警執法經驗的批判性詮釋分析，本文指出在決策階段表面遭到排除的政策主張—性交易應當合法化—並未停止其作用，而成為基層員警辯護其「消極執法」正當性的理據。這樣的消極執行則有著「衝突緩衝」的作用，它使得這個議題原本內含的框架衝突，不再發展成為另一波推動修法的政治對抗。然而衝突的緩衝有其代價：弱勢階級的賣淫者，在消極執法的過程中，成為禁娼政策「象徵性取締」的主要對象。 基進民主論者早已指出，沒有任何政策決定能夠完全免於排除，重點在於區辨哪些排除與壓迫是可以辯護的，而哪些不行，此一洞見對於我們面對爭議型政策時至為重要。本文揭露並解釋禁娼政策如何在執行上造成了階級歧視的非預期後果，此一分析應足以構成檢討性交易政策的實務基礎。藉此，本文強調爭議型政策的目標界定，特別需要藉由執行實務經驗的回饋，不斷地進行反省檢討，以降低不可辯護之負面效應。就此本文也顯示了批判詮釋型的政策執行研究對民主治理可以有的貢獻。

This paper explores the role and implications of implementation in controversial policies through a case study on the street-level police’s clampdown of prostitution. Since policy conflicts are always blamed for causing implementation failure, I am interested to know how exactly the “unsolved” policy conflicts might affect implementation and the implementers; what are the implications of “implementation failure” or “ineffective implementation”; and how the target population might be impacted. After performing a critical interpretative analysis on the police’s experiences, I argue that the excluded policy frame(s) at the policy formulation stage did not disappear, but were represented in the police’s “passive implementation.” Meanwhile, passive implementation as such serves as a buffer for the unsolved frame conflicts, preventing them from evolving into another wave of political or social confrontation. Yet the buffer costs: the burden of unsolved conflicts was shifted to lower-rank prostitutes, who appeared to be the main target of the police’s passive implementation. This paper aims to show how implementation research can contribute to not only the uncovering of excluded or ignored frames at the formulation stage, but also the practical impacts of such exclusion. Acknowledging that exclusion is inevitable for any policy, I argue that the point of policy analysis is to distinguish justifiable exclusion from unjustifiable one. In this sense, implementation research plays an important role for realizing democratic governance.