Thе narrow question presented by these appeals is whether a landlord’s action *205 for possession of premises has become moot where the record shows only that (1) counsel for both parties represented to the trial court when thе cases were called for trial that the tenants had vacated the premises sometime during an eight-month period betwеen the filing of the complaints and trial date and (2) counsel for the tenants (appellants) moved in open court to dismiss thе complaints for mootness. 1 The trial court upon these facts and without giving any reason refused to grant appellants’ mоtion and permitted appellee to prove its case. Thereafter, it made a finding of the rent due from each аppellant and entered judgments in favor of appellee. 2
This court has often ruled that where a tenant voluntarily surrendеrs possession of the premises during an appeal taken from a judgment of possession for the landlord the case is moot and the appeal is dismissed, since there is no longer any controversy remaining between the parties. Dietz v. Miles Holding Cоrp., D.C.App.,
The duty of this court, as of every other judicial tribunal, is to decide actual controversies by a judgment which can be carried into effect, and not to give opinions upon moоt questions or abstract propositions, or to declare principles or rules of law which cannot affect the mаtter in issue in the case before it. [Mills v. Green,159 U.S. 651 , 653,16 S.Ct. 132 ,40 L.Ed. 293 (1895).]
See also
Cardoza v. Baird,
Appellee contends, citing our decision in Hohensee v. Manchester, D.C.Mun.Apр.,
In the instant case, the unusual circumstances that existed in Hohensee were not present. Accordingly, we are of the opinion that the formal request by appellants’ сounsel in open court to dismiss the cases as moot was sufficient, taken with appellants’ departure from the leasеd premises, to constitute a voluntary surrender of the premises and an unequivocal acknowledgment of their landlord’s right to рossession.
Appellee also contends that it has a need for the entry of judgment for possession, or some other fоrmal order, establishing its right to reenter the defaulting tenants’ apartments. This is because, as a lessor of public housing,
3
it must seek to avoid accidentally displacing those tenants who leave leased premises without an explanation but who may later return and charge the appellee with wrongful entry. It seems to us that once the tenant
successfully
moves in open court through his attоrney to have the suit for possession dismissed as moot (and, of course, the disposition of such motion and reason therefоr will be noted and recorded permanently on the court’s docket), the tenant is thereafter equitably estopped from later asserting a claim to entitlement to possession. Jamison v. Garrett,
Under the circumstances of this case we conclude that the trial court should have granted appellants’ motions and dismissed the complaints.
Reversed and remanded.
Notes
. These eases constitute but a small number of possessory actions brought by ap-pellee against its public housing tenants who had apparently organized а rent strike to protest conditions on the premises they had leased from appellee.
. Although the suit was an
in rem
posses-sory action and not
in personam
for a money judgment for back rent,
see
Super. L & T, Rule 3, we have directed the trial court when it decides such actions on the merits to make a specific finding of the exact rent due and owing in order to permit the tenant at any time before eviction to pay his rent and avoid forfeiture of his tenancy. Tutt v. Doby, D.C.App.,
. See Rudder v. United States, D.C.Mun.App.,
. Appellee argues that appellants were es-topped from having these cases declared moot because at the time they moved to dismiss for mootness they had pending motions for summary judgment which they had filed before trial. But Parker makes clear that for estoppel to apply against a party to litigation that party must have asserted, successfully, one position in litigation, and then switched his position, after the other party has relied thereon to his detriment. In the instant case, appellants were not successful with their summary judgment motions and ap-pellee at no time, according to the record before us, relied to its detriment upon appellants’ assertions in such motions.
