Two police officers are being investigated after a community race relations adviser was mistaken for a wanted man and Tasered.
The pair are now being investigated for gross misconduct by a police watchdog following the blunder which saw Judah Adunbi, 63, hit in the face on January 14.
A video of the incident in Easton, Bristol, appeared to show Mr Adunbi refusing to give Avon and Somerset Police his name, before a brief tussle with a male and female officer, and the discharge of the stun gun.
The Independent Police Complaints Commission said it has served the two officers with gross misconduct notices as part of their investigation which is "progressing well".
IPCC Commissioner Cindy Butts said: "The incident in which Mr Adunbi was Tasered has attracted significant community concern and I am grateful to the representatives for their attendance last week and their honest and frank contributions.
"We would reassure them that we are conducting a thorough investigation into the circumstances surrounding this incident.
"The investigation is making positive progress and we are continuing to review evidence regarding the appropriateness of Taser use in the circumstances."
Mr Adunbi is a former member of the Independent Advisory Group to Avon and Somerset Police, which advises on policing issues.
Members from different backgrounds are invited to volunteer in a bid to promote good links between different communities.
Mr Adunbi was arrested and charged with a public order offence and assaulting a police officer. The charges were later discontinued.
The IPCC conducted house-to-house inquiries, obtained statements from a number of witnesses and collected guidance, procedures and policies over Taser use as part of the investigation.
It also viewed body-worn camera footage from the officers involved and took their statements.
The head of professional standards at Avon and Somerset Police, Richard Corrigan, said: "Today, the IPCC announced that it has served two officers with gross misconduct notices regarding the incident involving Mr Adunbi.
"We're continuing to co-operate with them as their investigation progresses but cannot comment on the circumstances surrounding the incident as a consequence of the IPCC involvement.
"Chief Constable Andy Marsh has promised that we will discuss the matter fully and publicly once the IPCC investigation has concluded."
