Question juridique clé
Whether the criminal-law limitation period had to be examined for fines converted into substitute imprisonment.
Solution extraite
The limitation defense is admissible before the Federal Court because the cantonal appellate court had full review powers and had to examine prescription ex officio.
Motifs extraits
A new legal ground may be raised when the last cantonal instance could freely review the case and had to apply the law ex officio; this was the situation in the cantonal appeal proceedings.