This relates to my last Fishbane post, Kidnapping Law, Part 2, in which I promised to compare the Hebrew of Exodus 21:16 and Deuteronomy 24:7 to determine if the latter used the former as a source. I’ve colored the words that are the same–or which have the same root–in both verses:
Exodus 21:16: ve-gonev ish u-mecharo ve-nimtsa be-yado mot yumat.
Deuteronomy 24:7: ki-yimatsei ish gonev nephesh me-echav mibnei yisrael ve-hitamer-bo u-mecharo u-met ha-ganav ha-hu u-varta ha-ra mi-kirbecha.
I think there’s significant similarity, so I can see why Fishbane believes Deuteronomy used Exodus in this case.