Speech by company executive contradicts denial by Trump campaign that claimed the company used its own data and Facebook data to help the campaign.

Cambridge Analytica used its own database and voter information collected from Facebook and news publishers in its effort to help elect Donald Trump, despite a claim by a top campaign official who has downplayed the company’s role in the election.

The data analysis company, which uses a massive database of consumer and demographic information to profile and target voters, has come under the scrutiny of congressional investigators who are examining the Trump campaign.

This week, the group became the focus of a new controversy after the Daily Beast reported that the company’s chief executive, Alexander Nix, had contacted Julian Assange last year. Nix allegedly asked the WikiLeaks founder whether he could assist in releasing thousands of emails that had gone missing on a private server that had been used by Hillary Clinton. Assange confirmed the contact but said the offer was rejected.

The news prompted a top former campaign official, Michael Glassner, who was executive director of the Trump election campaign, to minimise the role Cambridge Analytica played in electing Trump, despite the fact that it paid Cambridge Analytica millions of dollars in fees.

In a statement on Wednesday, Glassner said that the Trump campaign relied on voter data owned by the Republican National Committee to help elect the president.

“Any claims that voter data from any other source played a key role in the victory are false,” he said.

But that claim is contradicted by a detailed description of the company’s role in the 2016 election given in May by a senior Cambridge Analytica executive.

Speaking at a conference in Germany, Molly Schweickert, the head of digital at Cambridge Analytica, said that Cambridge Analytica models, which melded the company’s own massive database and new voter surveys, were instrumental in day-to-day campaign decisions, including in helping determine Trump’s travel schedule.

The company’s models also helped drive decisions on advertising and how to reach out to financial donors.

Schweickert said Cambridge Analytica started working with the Trump campaign in June 2016.

“It became obvious that a sophisticated data apparatus would be needed to combat the years of infrastructure and experience the Clinton campaign had been building up,” she said.

One of the company’s strategies was to work in “collaboration” with news publishers like Politico, the political news website, which Schweickert said helped the company target a political ad about the Clinton Foundation to readers in key battleground states.

“We knew we would be showing this to the right individuals,” Schweickert said.

In another case, in the late stages of the November election, Schweickert said the company acquired data on voters who voted early – data it collected from local counties and states – and linked the information to individual Facebook profiles.

This helped Cambridge Analytica determine whether people had been exposed to certain political advertisements, and whether those people had turned in their early voting ballots, helping them to predict the outcome of the election.

When asked by a German audience member whether this was legal, given privacy rules in Europe that would “probably” make the activity illegal in Germany, Schweickert responded: “It’s a very different sort of data privacy culture.”

“All the data we work with is already publicly available,” she said.