The CDC defines chloroacetophenone (CN) as tear gas https://www.cdc.gov/niosh/ershdb/emergencyresponsecard_29750...
Pepper balls contain oleoresin capsicum (OC) which is different in terms of its chemical composition but produces similar symptoms.
Depending on your definition, it may or may not be the same thing because "tear gas" is an unscientific term.
> Riot control agents (sometimes referred to as “tear gas”) are chemical compounds that temporarily make people unable to function by causing irritation to the eyes, mouth, throat, lungs, and skin.
I think we all agree that "gas/chemicals that cause tears" is "tear gas". Anyone saying that tear gas was not used is splitting hairs and their motivations should be questioned. This is not the time to be "technically correct" when police are using things like this on peaceful protesters.
[0] https://emergency.cdc.gov/agent/riotcontrol/factsheet.asp
By that standard, it's tear gas.
They want to say it was just smoke grenades and pepper balls... Which the CDC defines as "tear gas".