Police are generally more apt to use heavy responses including chemical weapons against Black protesters in general (Morman et al. 2020). It is therefore not surprising to learn that law enforcement use foggers to deploy chemical weapons on racial justice protests. Indeed, the first use of the fogger in the United States was during the Liberty City Riots, a police action in response to Black community organizations holding conversation among themselves.
Although mentioned in a few outlets during the 1992 police response to the protests in response to the verdict in the Rodney King case, I have yet to find documentation of used explicitly during that time (Askren 1992). For example, Riley County (Kansas; 1970 pop. 56,788; USCB (1971)) Sheriffs had a fogger in their arsenal in 1992 according to Director Alvan Johnson (Askren 1992).
The thermal fogger made a very visible return to the public sphere in July of 2020, when US Customs and Border Protection (CBP) officers brought a bright-green version to Portland, OR during the 2020 Black Lives Matter protests (PB2020 Team 2021). Since then, the fogger has been deployed three additional times by CBP in Portland, all at the property Immigration and Customs Enforcement (ICE) rents on the South Waterfront.