THe Roman Law Library is an excellent resource, the linguistically accessible parts being sub-forums 18&20
No. 18, Lingua Anglica, contains translated laws spanning 1600 years, from the Laws of the Kings from 8th century BC to (Byzantine) Emperor Leo around 900 AD
This contains the entire Corpus Juris Civilis by Justinian, in the unfortunate translation of Scott.
No.20 contains a huge amount of scholarly works, mainly from the 19th century.
For the Codex Justinianus, the collection of imperial edicts, there exists a much better online source, namely Justice Bluhme's translation: