Starmer's problem is that he is trying to portray himself as an upright citizen against Boris Johnsons lying and obfuscation. If a crack appears in his story, and he appears shifty, then his honest joe personna falls away and people will start to think they are as bad as eachother ( Whether they are or not, life ain't fair)
The 'mistake' (?) about Angela Rayner being there but they hadn't realised they had missed her name out because they were 'too busy' is I'm afraid straight out of the Boris Johnson play book. This story has been around for weeks.
Then there was the interview he gave to Sky (I think this week)which I heard part of on LBC where three or four times he refused to clarify whether or not he had heard from the police abour reopening the investigation. Later in the morning his office said that they hadn't heard from the police so why didn't he just say this
Finally there was his reaction to the news that the Durham Police were going to reopen the investigation.Instead of stopping for a brief word when asked about it by journalists he ignored it and walked on with that 'I didn't hear you' demeanor which all politicians adopt when you know damn well they had heard every word.