The Association of Garda Sergeants and Inspectors (AGSI) is to write to the Garda Commissioner after verbal abuse was allegedly directed towards a member.
The association said it happened at a Covid-19 checkpoint in Dublin yesterday.
The AGSI strongly condemned what it describes as the "abuse and vitriol" faced by one of its members at the checkpoint.
It said a video posted on social media, which has had over 122,000 views, shows an officer being subjected to "abuse and threats".
The association's General Secretary Antoinette Cunningham described it as totally unacceptable, saying it crossed the line of acceptable questioning of gardaí's role in the public health crisis.
"Threats such as ‘this is coming to an end very soon’ and ‘you will be reminded who is in charge and who are your masters’ and abuse such as ‘you are a disgrace to this country’ is despicable behaviour towards frontline members playing a crucial public health role – members who are putting their own lives at risk," Ms Cunningham said.
She said she will be writing to Commissioner Harris to express the group's deep concern on the matter.