When Mark Zuckerberg testified before Congress in October, the Facebook founder and chief executive faced pointed questions about his decision to exempt politicians from a policy barring advertisers from promoting false claims – or to put it another way, his decision to allow politicians to spend money to promote lies.

“This isn’t about helping the politicians,” he told congresswoman Rashida Tlaib. “This is about making sure that people can see for themselves what politicians are saying.”

Since the 2016 election, during which Facebook allowed candidates to purchase so-called “dark ads” that could only be seen by whatever narrow slice of the electorate they were targeted at, Facebook has promised to provide more transparency by building a political ad archive. If you want to know how your local city council candidates are selling themselves to the electorate on Facebook, you can navigate to a relatively user-friendly site and see exactly what they’re saying.

So far, so reasonable, right?

Not exactly. Over the past week alone, Donald Trump’s re-election campaign has run more than 16,000 different advertisements on Facebook. And that’s just one week, just one candidate, and just Facebook! At any given moment, the Trump campaign will have between 1,000 and 5,000 different ads running simultaneously. If you want to take a peek, head to this link and start scrolling. Chances are you’ll give up – or the page will freeze – before you get to the bottom.

Many of these ads are minor variations on a single theme, targeted at narrow slices of the electorate in ways that are opaque. This lack of transparency reveals the dishonesty in Zuckerberg’s claims that Facebook supports the democratic process by allowing people to “see for themselves what politicians are saying”. Not to put too fine a point on it, but it’s utter bunkum.

Calling out Silicon Valley’s deceptions and distortions is something of a Guardian US tradition. Since we opened our west coast bureau in 2016, we’ve worked overtime to expose the gaps between the tech industry’s altruistic rhetoric – and the reality of how tech companies are reshaping society. We pride ourselves on making sure that Guardian values shape the questions we ask: whose labor went into that billion-dollar valuation? Who is being left out of a company’s rosy picture of the future? What does this mean for privacy? How do decisions made in Menlo Park affect people in Myanmar, Brazil, Hong Kong or the west coast’s numerous homeless encampments?

This year, we exposed allegations of wage theft by one of the richest companies in the world, revealed how Amazon was working with police departments to create a vast surveillance system and held social media platforms accountable for amplifying anti-vaccine misinformation – reporting that inspired action from the congressman Adam Schiff. We tracked extremism and hate from the dark corners of the web to the supposedly sanitized realm of Facebook, reported on the harsh reality of Uber drivers living in their cars as the founders made off with billions, and showed how the boom in “kidfluencers” was enabling exploitation of child labor.

Looking ahead to 2020, we’re getting ready to track misinformation and digital campaigning in a momentous election for US politics. Unlike Zuckerberg, we won’t pretend to believe that any individual person can read and understand 16,000 advertisements a week. We know that democracy depends on our work helping readers cut through the piles of lies to discern fundamental truths.

But we can’t do it without your help. Now through January, we hope to raise $1.5m to fund our journalism in 2020.

Please consider making a contribution. And as always, thanks for reading.