We don't trust politicians. We do trust public broadcasters. So when politicians cut funding to public broadcasters, expect to see a loss of public trust, write Peter Lewis and Jackie Woods.

Perhaps Tony Abbott thought his now-famous pre-election "no cuts" line was more believable because he said it on the SBS news.

After all, in a climate of general cynicism and suspicion, our public broadcasters stand out as rare institutions the public reward with their trust.

As the impact of the ABC cuts announced yesterday is digested in newsrooms and living rooms around Australia, there is intense interest in whether the "lie" (alleged) will damage Tony Abbott politically.

Abbott has followed his frontbenchers in insisting his "no cuts" line was misunderstood rather than misspoken, and that the ABC must take its efficiency medicine like everyone else. Meanwhile, the headcount of forced redundancies grows and communities from Morwell to Newcastle to Adelaide count the local cost of cuts.

But the fallout from this week's announcements must be considered against bigger trends: a rapidly changing and fragmenting media landscape and a collapse in trust in our political and public institutions.

Tony Abbott made his "no cuts" promise because he knows cutting the ABC isn't popular. Our polling consistently shows majority opposition to cutting funding to the ABC, and this week is no different.

There has been a shift among Coalition voters, who are now more inclined to support the Government's cuts to the ABC budget. But overall, only a quarter of voters approve the funding cuts while more than half disapprove.

While specialist programming and regional services are an important factor in opposition to funding cuts to our public broadcasters, another is simply that they are trusted media sources.

Voters rate the ABC and SBS significantly higher than their commercial counterparts in trusting what they hear.

ABC news and current affairs comes in 23 points higher in trustworthiness than its commercial counterparts; ABC radio talkback 15 points ahead of commercial talkback. And apart from the headline figures, we see a trend over time of trust decreasing in commercial outlets while trust in public broadcasters generally holds steady.

Audiences understand that the commercial imperative for clicks and ratings doesn't always line up with believability.

This trend coincides with a political climate where trust in politics and public life has plummeted.

During the Gillard years, Essential tracked a collapse in trust in politics and public institutions as the political fight over carbon pricing and that other lie saw voters put a pox on all their houses.

As the numbers during 2012 showed, the bitter wrangling in Canberra saw a collapse in confidence not only in politicians but in all our public institutions from the High Court to Parliament to the Reserve Bank.

Low levels of trust in public institutions have persisted into 2014. News programs aside, the ABC fares well as a trusted institution, second only to the High Court and winning double the trust of Federal Parliament.

While the semiotics of Tony Abbott's "no cuts" lines are being robustly contested - the government determined not to descend into a "no carbon tax"-style credibility disaster - there's a bigger issue of trust at stake.

We don't trust politicians. We do trust public broadcasters. Politician cuts public broadcaster is an equation that can only lead to a net deficit of public trust.

Peter Lewis is a director of Essential Media Communications. View his full profile here. Jackie Woods is a communications consultant at Essential Media Communications. View her full profile here.