Tzlach Berachos 7b:
????? ??? ???? ?????? ??????? ???? ?????? ????”? ??’ ?????? ?? ?’ ???? ????? ????? ??? ??? ????? ??????? ??? ??? ????? ??????? ??? ??’ ???? ??? ????? ????”? ??? ??? ??? ?’ ?????? ?? ???? ?????? ??? ??? ????? ???, ?? ????”? ????? ?????? ??????? ??? ????? ???? ????? ?? ??? ??? ??? ???? ?? ????? ???? ?? ?????? ???? ?????? ?????? ??? ?????? ?? ????? ????? ??? ??? ?? ??????? ?? ???’ ??????? ???? ??? ?????? ???? ?????
So it is clear that “halacha” and “hanhaga” are two different categories which have different rules governing the decision-making process.