Theresa May has embarked on a "vindictive and punitive approach of hanging someone out to dry" for relaxing border checks, former home secretary Jack Straw said.
The Home Secretary is under intense pressure after border force chief Brodie Clark quit his job and accused her of misleading Parliament, saying she was simply blaming him for "political convenience".
Mrs May answered questions over the security of the UK's borders for a third day amid Labour MPs' calls for her to resign over the scandal, which could have allowed an unknown number of foreign terrorists and criminals into the UK.
"What a great shame that the Secretary of State has jumped impetuously to a conclusion without any proper evidence, without allowing others to respond to that," Mr Straw said.
"At the heart of this debate is the conduct of the Home Secretary and the level of ministerial responsibility - both for competence in running the department and moral responsibility for what happens in that department.
"The whole system will seize up unless those who are lower down in the system believe those at the top have their confidence and are ready, when things go wrong, to take responsibility.
"You have to ensure you take the majority of the staff with you.
"What you don't do - and I'm sorry the Secretary of State has embarked on this - is go for what appears to me, whatever her personal motives, both a vindictive and punitive approach of hanging someone out to dry because it appears to her that would be a good way of saving her career."
In a scathing parting shot, Mr Clark flatly denied "improperly" extending a relaxation of entry controls and said he was suing for constructive dismissal.
The dramatic intervention was swiftly countered with a statement from the UK Border Agency (UKBA) chief Rob Whiteman, insisting Mr Clark had admitted going beyond ministerial orders.
Read More
MORE ABOUT