Well they have already begun.
The former head of the UK border force Brodie Clark has told MPs he is "no rogue officer".
Home Secretary Theresa May suspended Mr Clark after claiming he relaxed passport checks at UK borders beyond what she had agreed to in a trial.
He then stepped down, saying his position had been made "untenable".
He "did not extend or alter" the pilot "in any way whatsoever" and was "meticulous" in ensuring senior staff were briefed on it, he told MPs.