For most small employers, there is no reason that these processes cannot be carried out remotely, ideally via video conference, if not, by a telephone conference call.
If an employee is on furlough, ACAS suggests that employees can participate if they do so voluntarily.
The employees managing the process are likely to be deemed working so would have to come off of furlough.
Delaying an investigation a number of months may be an issue in terms of fairness i.e. memories fade, also if it is serious why would you want to delay?
It may be relevant to consider during the investigation and the context of lockdown, i.e. are there other factors? For example, if there is an issue with poor performance before disciplinary action is considered, the manager should review the amount of support given to an employee while working remotely and consider if the employee is showing behaviours that out of character since working at home.
These are difficult times for both managers and their teams and business will need to consider the best way to proceed, our clients find it helpful to have a confidential discussion with us before taking action.