Since our focus here at ProPublica is on investigative journalism, we’d like to give a nod to the reporters whose investigative stories won or were finalists for Pulitzer Prizes this year.

David Barstow at the New York Timeswon the prize for investigative reporting for his story on the Pentagon’s "message machine." Barstow detailed how the Pentagon got former generals to put a positive spin on the Iraq war as supposedly impartial analysts on major television networks. What’s more, many of the analysts had undisclosed financial ties to defense companies that raked in huge profits from the war.

Paul Pringle at the Los Angeles Times was a finalist in this category for his exposure and continuing coverage of financial abuses by the head of California’s largest union. His reporting prompted an investigation by Congress and the U.S. Labor Department, tougher federal disclosure rules for unions, the union official’s resignation and the eventual repayment of funds.

Susanne Rust and Meg Kissinger at the Milwaukee Journal Sentinel were the other finalists for their story on the federal government’s failure to protect the public from dangerous toxins in "microwave-safe" containers and other products, spurring Congress and federal agencies into action.

Investigative stories won in two other categories as well. Alexandra Berzon at the Las Vegas Sunwon the public service prize for exposing how safety shortcuts and lax regulation led to the deaths of 16 construction workers on the Las Vegas Strip. The Detroit Free Pressshared the prize for local reporting with the East Valley Tribune. The Free Press’ story about the then-mayor of Detroit’s lies to cover up an extramarital affair with an aide had incredible impact: It resulted in a perjury investigation and subsequent jail terms for both the mayor and the aide.

Update: An earlier version of this post said the Milwaukee Journal Sentinal story was nominated; it was a finalist, and this version reflects that change.