Facts
In this case, the landlord Alfred B. terminated the lease of his tenant Heinz L. for non-payment of rent. On 15 July 1991, the landlord sent a registered letter to the tenant granting a 30-day deadline to pay the outstanding rent, with a threat of termination. The tenant received this letter no later than 20 July. Believing that the 30-day deadline had already started on 16 July, the landlord terminated the lease on 14 August, with effect as of the end of September. On the same day, the landlord filed a request for the eviction of the tenant with the District Court of Pfäffikon/ZH. The single judge, as the eviction judge, granted this request on 29 August, after finding the termination to be valid in accordance with Art. 274g para. 1 let. a CO. On appeal by the tenant, the Supreme Court of the Canton of Zurich confirmed on 12 November the eviction order and the validity of the termination, even though it had been pronounced before the expiration of the 30-day deadline. The tenant then filed a nullity appeal against this decision, which was rejected on 2 March 1992 by the Court of Cassation of the Canton of Zurich.
Considerations
The central question is whether the eviction judge was competent to rule on the validity of the termination contested by the tenant, when it had been pronounced during the 30-day payment deadline. The Federal Tribunal considers that federal law takes precedence over cantonal law, which limits the competence of the eviction judge to only undisputed ("liquid") claims to be judged in summary proceedings. In this case, the law was not clear, as there was no established case law or unanimous doctrine on the validity of a…