新住民相關親權酌定裁判書的文字探勘：對「平等」問題的法實證研究嘗試

Applying Texts Mining on Child Custody Cases Regarding New Immigrants in Taiwan: An Empirical Study on Equality

本研究關心新住民與我國籍配偶離婚後，進入法院爭取未成年子女親權時，是否獲得平等對待之問題。本文使用資訊科學技術，驗證「法院是否會因父母的國籍而在裁判書中使用不同的詞彙」，分析116件親權酌定事件之裁判書。其中有31件之一方當事人為外籍、外裔人士（簡稱外籍裁判），85件為雙方當事人皆為我國籍（簡稱雙臺籍裁判）。首先，將裁判書中的詞彙在分詞後，轉化為TF-IDF的文本詞彙矩陣，再透過主成分分析投影在二維平面上，將每則裁判書的詞彙特徵（所在位置）可視化。雙臺籍裁判與外籍裁判並未分為不同的兩群，而是位置重合，意味著法院在兩種當事人的裁判並未使用不同的詞彙，因此無法直接主張司法體系對新住民不平等。其次，再使用機器學習中的梯度提升法，發現外籍裁判中，「是否出境」以及「居住狀況」相關詞彙特徵，較雙臺籍裁判為高，表示法官在外籍裁判中較關心程序參與以及居留問題。藉由文字探勘與機器學習來分析裁判書文本，除了檢驗平等問題外，還可將抽象的法律概念（子女最佳利益）具象化為裁判書中提及之事實（出境、租屋），供實務參考，結合了資訊與法律兩個領域，呼應本刊「跨域、科技與法律」的主題。

There are more and more transnational (international) marriage cases in Taiwan today. As an ethnic group, the New Immigrants are facing multiple issues regarding equality/ inequality in daily life. This article attempts to find if a foreign spouse is treated equally in child custody proceedings in Taiwan. In detail, we studied 116 real legal texts (judgements) by Natural Language Processing (NLP) and Machine Learning (ML) in which 31 foreign cases are included. Firstly, after word segmentation, the document-term-matrix of TF-IDF is produced and then put into principle component analysis so that a two-dimensional plot is formed. It is thus found that 85 domestic marriage cases and 31 international marriage cases are almost located at the same place, meaning that the court does not use different vocabularies between these two types of cases. It indicates that the family judges did not treat or judge the New Immigrants differently from domestic couples. Secondly, using gradient boosting of machine learning, it is found that the vocabulary characteristics of cases involving New Immigrants are: “whether one party appears at court”, “renting a house”, and “living together”, indicating that judges are more concerned about the participation of procedures and residence of New Immigrant parents. If a foreign spouse obtains legal aid and participates in the judicial process, since the standard adopted by the judge on the child custody is the same on both New Immigrant cases and domestic marriage cases, it is very possible that the foreign spouse will receive custody. However, the foreign spouse may need to acquire other social support on housing as it is a factor that family judges tend to investigate in New Immigrant cases. In this paper, the authors adopt disciplinarities of information science and law, showing one of the possibilities in which technology helps us to deepen the discussion of social responsibility.