McAuley was given a 12-year jail term, with the final four suspended, after being found guilty of a two-hour, frenzied attack on his wife, on Christmas Eve last year.
Pauline Tully was stabbed 13 times in front of the couple’s children. However, with remission, McAuley, 50, could be released in five years.
Sinn Féin deputy leader Ms McDonald yesterday said that, given the “scale and viciousness” of the attack, she believed the sentence, which was handed down in Cavan Circuit Criminal Court, was extremely lenient.
McAuley was previously given a 12-year sentence for his part in the killing of Garda Jerry McCabe, who was shot dead while on duty in Adare, Co Limerick, in 1996.
He admitted to falsely imprisoning Ms Tully at the family home in Kilderry, Kilnaleck, Co Cavan, and to assaulting her, on December 24 last.
Ms McDonald said: “It is not for me to direct the courts to the level of sentencing, but I would say this: I believe, in this case, as in many, many others, it seems to me that the sentence delivered is very, very lenient, given the violence and trauma and the terror that was visited on that woman and her small children.
“I should say that Pauline Tully is a friend of mine, she is a person that I know for a very, very long time. She and her two small children went through an unspeakable trauma.”
Last year, abuse victim Mairia Cahill was highly critical of Ms McDonald after she refused to accept some of her claims that she was raped by a republican member and dealt with by a “kangaroo court”.
At the time, Ms McDonald had said she was “deeply sorry” for the “horrific” nature of the abuse, but also said that claims that the party had covered up the abuse were “simply untrue”.
Ms Cahill said that Ms McDonald had “treated a victim of sexual abuse shamefully in public”.
Separately, Ms McDonald yesterday dubbed as ‘Coalition-gate’ reports that her party had not ruled out going into partnership with Fianna Fáil.
Although Sinn Féin would not be willing to “prop up” a larger conservative party, she said the party would be open to talking with any groups who shared their ideas.
“They [Fianna Fáil] may have a road to Damascus conversion, and if they do that’s fantastic, because the more that the ground shifts towards a progressive situation, where politics serves the people and where Government serves the collective good, in our view that’s a good thing,” she said.
“I think the position has actually been put out very, very clearly: Sinn Féin wants to be in government.
“We will not be propping up any large conservative party.”