The General Secretary of the Garda Representative Association is to step down from his position, after the executive voted not to renew his contract.
Pat Ennis has been in the post for the last three-and-a-half years.
61% of the Central Executive Committee voted to retain Mr Ennis, but association rules say two thirds are required for him to remain in the position.
He was a member of An Garda Síochána when first appointed in 2016 and continued in the job when he retired.
Mr Ennis is to step down after the GRA annual conference in April when his contract expires.
The GRA is the largest garda association, representing over 12,000 rank and file gardaí.
A GRA spokesman said they were not commenting at this time.
The president of the GRA said that the loss of Mr Ennis has been greeted with "consternation" by many rank and file gardaí.
Jim Mulligan said the vote at the Central Executive Committee not to renew Mr Ennis' contract does not reflect the view of the majority of the membership.
Mr Mulligan said Mr Ennis brought forward a reform agenda and performed his job with diligence, integrity and skill.
He also said that he had wholeheartedly endorsed Mr Ennis to continue in the role as General Secretary.