Journalists are generally not required to disclose their source. They only have to take reasonable steps to verify their story, and provide some (hopefully) credible evidence to substantiate it and have a so called public-interest reason to publish the story.
Even if they only present the story as an allegation, it shifts the burden of proof to the target person of the story, instead of the source of the information. ( Harber, 2020)
It follows that the media can publish information, which is supposedly in the public interest, fairly quickly. The problem arises when the journalist does not conduct proper fact checking, verifying the evidence, critically analysing where the story emanates from and what it signifies, putting it into the correct context, and most importantly, offering a genuine and substantive right of reply. If they do not do the aforesaid, they can be used by those who leak disinformation to them for personal, political or financial gains.(Harber, 2020)
This danger becomes even more pronounced when a newspaper is under financial pressure; so much so that the need for a big front page story often clouds their judgement and is published unfiltered and unchecked (Harber, 2020).