Not civil law vs common law, or, common law vs continental law [1]
In using the Constitution as a living document which can be interpreted by an activist judge, rather than the constitution as written [2], as passed by the states/amendment (originalism), interpreted by precedents from the collection of rulings, and caselaw.
[1] https://www.lawteacher.net/free-law-essays/constitutional-la...
[2] https://www.swindlelaw.com/2017/10/originalism-living-consti...