"The more serious the offence committed by a foreign criminal, the greater is the public interest in deportation of the criminal." 24. This steers the tribunals and the court towards a proportionate assessment of the criminal's deportation in any given case. Accordingly the more pressing the public interest in his removal, the harder it will be to show that the effect on his child or partner will be unduly harsh. Any other approach in my judgment dislocates the "unduly harsh" provisions from their context. It would mean that the question of undue hardship would be decided wholly without regard to the force of the public interest in deportation in the particular case. But in that case the term "unduly" is mistaken for "excessive" which imports a different idea. What is due or undue depends on all the circumstances, not merely the impact on the child or partner in the given case. In the present context relevant circumstances certainly include the criminal's immigration and criminal history…. 26. For all these reasons in my judgment MAB was wrongly decided by the Tribunal. The expression "unduly harsh" in section 117C (5) and Rule 399(a) and (b) requires regard to be had to all the circumstances including the criminal's immigration and criminal history. "