Sheridan's dismissal in the wake of nine successive defeats, but Hardy has revealed that Sheridan was removed from his position because of verbal abuse towards a fourth official in December.
A transcript of Sheridan's expletive-laden rant was made public earlier this month, and that has led to Hardy clarifying the circumstances of the 52-year-old's exit.
Hardy told the club's official website: "It was our decision to terminate the contract based on what I read in the referee's report regarding the incident. This is a family-friendly club which aims to be a pillar of the local community.
"In light of the recent disclosure of the referee's report, I thought it appropriate to communicate the exact reasons behind the course of action we took."
Sheridan has since been appointed as the new boss of League One side Oldham Athletic.