With only one untitled member of the cabinet, the new ministers were hardly foaming radicals. Nevertheless, the Bill given its first reading in March 1831 caused stupefaction. In addition to establishing a lower property qualification for the franchise, it abolished rotten boroughs and reallocated seats to the industrial cities. As Robert Peel, Tory leader in the Commons, sat with his head in his hands, the Bill's clauses were greeted with "wild ironical laughter", while one Tory member repeated incredulously, "They are mad!"

After making early progress, the Bill was defeated in committee, whereupon Grey asked the king for an immediate dissolution. To his wife's annoyance, the initially reluctant king became so eager that, on being told that the royal carriage could not take him to Parliament until the horses' manes had been plaited, he shouted, "Then I will go in a hackney coach!" 

At the subsequent general election a pro-reform majority was returned, and after an exhausting struggle the Bill was piloted through the Commons. Yet the unelected House of Lords still posed a seemingly insuperable obstacle. When the Bill was defeated there on October 4, national resentment threatened to become uncontrollable. There were riots in Nottingham, Derby and Bristol, resulting in 400 deaths in the latter city. It was fortunate that the Birmingham Political Union, the main pressure group advocating Reform, remained against violence, counselling its supporters, "Patience! Patience!"

The Bill was resubmitted to parliament, but seemed doomed without a mass creation of peers. Grey understood that the king would do everything necessary. However, when — despite warnings that Britain was set to become "one scene of blood and terror" — the Lords rejected the Bill for a second time, the king reneged on his undertaking. In May 1832, he asked Wellington to form a government, albeit on condition of introducing mild Reform.