Sadly, the situation is not yet in the past tense and is in progress. Yoon was impeached and impeachment is being litigated in the Constitutional Court. Yoon is arguing some ridiculous excuses which would have been funny if this was not serious.

For example, martial law decree no. 1 said "Activities of national assembly, local assemblies, political parties, and all political activities such as political association, assembly, demonstration are hereby forbidden". Decree was widely published and it is a strong evidence that Yoon intended to violate the constitution and disable the legislative branch. Yoon is now claiming "it was copy and pasted from old authoritarian martial law decrees by mistake". No, really. It doesn't make any sense by itself, but moreover, this can't possibly be the case because South Korean local rule was introduced after democratic transition so no mention of "local assemblies" is possible in old decrees. I mean, lying is pretty difficult, reality has surprising details...