The City Council voted Thursday to greatly increase oversight of the New York Police Department and of its widespread use of stop-and-frisk tactics.

Coming after historic crime declines stretching 20 years and aimed at a police force whose tactics long enjoyed strong support in City Hall and among many New Yorkers, the move on two bills marked a decisive swing of the pendulum toward reining in the practices of officers and the policies of their leaders.

The votes, a week and a half after a federal judge ruled aspects of police stops in the city unconstitutional, amounted to a stinging personal defeat for Mayor Michael R. Bloomberg. He has considered the policy to be central to one of his main achievements: a city safer than many hardened residents had thought possible.

The two bills, which the mayor had vetoed and will now become law, represented an effort by frustrated elected officials to force changes on the police from the outside — one through an outside inspector general with subpoena power to study and make policy recommendations to the department; and the other by opening state courts up to individual claims of bias-based policing and by expanding the categories of people entitled to sue.