We used to defer this to journalists, effectively. While individual journalists often lied and misrepresented the truth, there was some responsibility within the industry to tell the truth, and newspapers did print retractions and corrections when they got it wrong. The editorial content was strictly separate from the business of running the newspaper, so editorial decisions were (mostly) not influenced by commercial decisions and free to pursue The Truth as they saw it.
That, sadly, is no longer the case. And we have no good replacement for it.
There is no incentive to be truthful currently, among democracies the seems to be most powerful in the US with Trump able to lie and there seemingly be no counter for it.
With old regulated media there was (is?) the legacy of the organisation and the idea it was "trustworthy" on the line for the journalists that work for it. So they have an incentive to be truthful, and hopefully an idea that publishing lies is not a good moral choice.
With the personality driven journalism that emerges from the internet there is less incentive to be truthful, such personalities can be very successful using populism alone to play to their audience.
