0 present participle of scupper
1 to sink your own ship on purpose
2 to cause something such as a plan or an opportunity to fail:
I was suddenly in a home where the staff were not supportive; frankly, they were scuppering.
Putting forward theses such as yours is a sure-fire way of scuppering the whole idea of a criminal court.
That had the effect of scuppering that campaign of personal harassment and defamation.