After heated debate, the bill passed through Parliament.
Literal
Bill [topic-は] heated debate [after-ののち] Parliament [object-を] passed
ののち (の後) is a formal/written equivalent of の後で ('after'), attaching to nouns for 'after X'. 激しい論争 = 'heated debate, fierce dispute'. 通過する ('to pass through') is the Sino-Japanese verb form used for bills clearing legislative stages.