Key questions facing government over Mandelson vetting

The prime minister will appear before MPs on Monday to explain what went wrong, after it emerged that Lord Mandelson did not pass inital security vetting checks ahead of taking up the role of ambassador to the United States.

But there are some key questions that remain unanswered.

Did the prime minister and the government mislead MPs - and the public?

The PM says he only found out this week that Lord Mandelson had failed developed vetting.

Questions were being asked in September last year - including by The Independent, which reported, that Lord Mandelson may not have passed the process.

Why did the PM therefore say at the time that 'full due process' had been followed?

And added to that question: why in February this year did he go further, saying there was "security vetting carried out independently by the security services... gave him clearance for the role"?

Which leads to the next question...

Why weren't more questions asked by the PM and his team?

Given journalists were asking about Lord Mandelson failing vetting, should No 10 have been more curious?

No 10 said there had been repeated requests for "assurances" from the Foreign Office about the "facts of this case", including vetting.

Why did Mandelson fail vetting?

Developed vetting is said to be a highly personal process. It's unlikely we will see full details of the questions asked and answers given.

But will the public be told what the concerns were?

Why were those concerns overruled?

And alongside that - why did officials in the Foreign Office make the decision to go ahead with the appointment?

Lord Mandelson's job had already been announced - would it have been too embarrassing to cancel it? Or were mitigations found to address the concerns? At the moment, we simply don't know.

What will Labour MPs do?

Plenty of Labour MPs are angry with the prime minister - and have been for some time.

They didn't act earlier this year when there were calls for the prime minister to quit. Will that change this time?

At the moment, many are busy campaigning ahead of May's elections in Scotland, Wales and for some councils in England.

Some are speaking up, but I don't yet detect a groundswell of pressure.

The PM's answers on Monday, when he makes a statement in the House of Commons, will be studied closely.

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