Point of Orderpublished at 15:03 British Summer Time 20 September 2017
Labour MSP Neil Findlay says this is supposed to be a debate and Mr Mackay is taking the "Ruth Davidson rape clause approach" in ignoring interventions.
Presiding Officer Ken Macintosh says Mr Mackay can decide whether to take interventions and he has taken one.
Mr Mackay says it is an "appalling contribution to such an important matter.