The Observer and Guardian reporter Carole Cadwalladr has won the Orwell journalism prize for her investigation into the collapsed political consultancy Cambridge Analytica.

The prize is awarded by the Orwell Foundation for the best political writing of the year, with the support of the family of the writer George Orwell.

Carole Cadwalladr’s Cambridge Analytica story in the Observer. Photograph: GNM

Cadwalladr said her experience of reporting the story, which resulted in the Facebook founder Mark Zuckerberg issuing a public apology for the misuse of user data, had been “like being strapped to a freight train for the last 18 months”.

“What we are seeing here is a systemic failure,” Cadwalladr told an audience in central London after collecting the prize. “Our laws do not work and our regulators are unable to regulate. We do not have the information we need from the big tech platforms.”

The judges praised her “whole set of amazing stories” and said they believed that “if George Orwell had been here he would have been unanimous in choosing our winner”.

The Orwell prize for exposing Britain’s social evils went to Sarah O’Connor, John Burn-Murdoch and Christopher Nunn of the Financial Times for their study of the British towns left behind by the modern economy.

The Orwell book prize went to a visibly overwhelmed Darren McGarvey, also known as the rapper Loki, for his book Poverty Safari, which explores deprivation in Glasgow. It was described as “not just an excellent example of political writing” but also “a book which needed to be written”.

Meanwhile, the Crick prize for the best article in the journal Political Quarterly went to Helen Thompson of the University of Cambridge.

The prize-giving was preceded by a debate on the impact of the Grenfell Tower disaster on society. The writer Anthony Anaxagorou, who lost friends in the fire, urged the public “to read more critically between the lines and to want more from their journalism”.

Orwell’s son Richard Blair, who helped present the prizes, said his father would have cast a critical eye over the Grenfell disaster and the media response. “Were he alive, and had this happened in his time, he would have very quickly cut through a lot of the obfuscation on all sides – both press and government.”