In: "soc.culture.jewish FAQ: Torah and Halachic Authority (3/12)"
[Topic: WHEN ORTHODOX RABBIS DISAGREE ON A RULING, as opposed to a disagreement on a ruling between an Orthodox and a Reform rabbi]
The Orthodox rabbis would both say that their halachic rulings are in line with the tradition of Torah learning*, all the way from Sinai, and that their difference is in details. The Reform rabbi, however, might derive a ruling from other sources of morality, such as secular ethical notions of equality.
the Orthodox scholars believe there was no disagreement over first principles, while Orthodox and Reform differ significantly on major principles, such as Torah being from G-d, and the authority of individuals to decide halacha for themselves.
* Refers to the Oral Law as well as the Written Law [editor's note].