The tenant or a person residing in or visiting the dwelling-house—
(a)has been guilty of conduct causing or likely to cause a nuisance or annoyance to a person residing, visiting or otherwise engaging in a lawful activity in the locality, or
(b)has been convicted of—
(i)using the dwelling-house or allowing it to be used for immoral or illegal purposes, or
(ii)an indictable offence committed in, or in the locality of, the dwelling-house.
Both are discretionary grounds, which mean that the Court must also be satisfied that it is reasonable in the circumstances to make a possession order and that the court has a further discretion to impose a postponed or suspended possession order with conditions.