The Guidelines on impartiality say “Our audiences should not be able to tell from BBC output the personal opinions of our journalists or news and current affairs presenters on matters of public policy, political or industrial controversy, or on ‘controversial subjects’ in any other area”.  The Guidance on the use of social media says “Individuals involved in the production or presentation of any output in News or other factual areas that regularly deal with a range of public policy issues have a particular responsibility to avoid damaging the BBC’s impartiality” and that “Nothing should appear on their social media accounts which undermines the integrity or impartiality of the BBC”.  The comment retweeted by Ms Maitlis (made in response to an interview in which the Secretary of State for Culture defended the Government’s position on parties in Downing Street) was “The sheer tawdry Trumpian shabbiness of the whole thing - it is difficult to see how much more of this the party or our political system can survive”.  The ECU judged that, in the absence of any indication to the contrary, retweeting the comment risked giving the impression that Ms Maitlis endorsed the view it expressed.  This was not in keeping with the Guidelines and Guidance quoted above.  However, Ms Maitlis posted two follow-up tweets before the complaint came to the attention of the ECU, the second of which said “for the avoidance of doubt I accept I should have added extra context – it was retweeted in haste – and was wrong to do”.  In the ECU’s view, this was sufficient to resolve the issue of complaint. 
Resolved