Inspired by the Totenkopf, which is a symbol for death, defiance, danger, and piracy, the punisher skull was created for the character Frank Castle by John Romitat and Ross Andru. It has become controversial as police and servicemen wear these punisher skulls while arresting protestors for protesting against police brutality and the violent murder of George Floyd. Marvel has not fully commented on the use of the skull, however they have stated “We stand against racism. We stand for inclusion. We stand with our fellow black employees, storytellers, creators, and the entire black community. We must unite and speak out.”
Source: https://io9.gizmodo.com/as-the-punisher-skull-re-emerges-on-cops-in-u-s-protes-1843911179