Nineteen police officers and staff are being investigated over comments they made on a website in support of a colleague facing disciplinary action.
Nineteen Pcs and staff now face disciplinary action
The Pc is under investigation after a suspected burglar was slightly injured during an arrest in Northampton.
The inquiry centres on messages of support his colleagues left on Facebook.
Det Supt Charles Moffat, of Northamptonshire Police described their comments as "inappropriate."
The officer being investigated was in a car pursuing an 18-year-old cyclist, who was suspected of burglary, when a collision occurred in Weedon Road.
The Independent Police Complaints Commission (IPCC) is now investigating the incident.
It is a decision which has upset his colleagues, who have posted comments of support on the Facebook site, including: "Keep smiling mate, you're a good hard working copper".
Other posts read: "Chin up, you're an inspiration to us all, everyone's rooting for you", and "you're a diamond geezer and the cream of the crop of an officer...."
But Det Supt Charles Moffat said: "The investigation is looking into their use of this site for such a purpose because it's clearly inappropriate to be discussing ongoing investigations in an open forum that is not secure.
"I've issued an instruction that as well as that being inappropriate, staff should exercise some caution in the use of these sites which are not secure and it could lead to the identification and danger of themselves their colleagues and their families."
It is understood the officer has been confined to desk work while the independent investigation, in which CCTV footage of the collision will be analysed, is completed.
Further action against the officer could follow.