"I don't exactly know what she is going to say about it during the debate," Clinton's running mate told CNN's Jake Tapper in an interview that aired Sunday on "State of the Union." "I think it's time for Donald Trump to answer and take responsibility."
The town hall debate, which will be moderated by CNN's Anderson Cooper and ABC's Martha Raddatz, will have 100 undecided voters in attendance who will have the opportunity to ask questions of the candidates.
"I just can't imagine that undecided voters as part of this town hall will not want to hear him explain why he thought that was acceptable behavior," Kaine said.
Asked about the newly released audio of a 2005 conversation in which Trump brags about being to grope women and get away with it, Kaine said: "It is not just words; it is talking about a pattern of sexual assault."
"There's plenty of evidence that this is exactly who Donald Trump is today, and by this, I mean divisive and cavalier in his treatment of others, and with respect to women in particular. What this shows at its base is that he cannot consider women as his equals," Kaine told Tapper. "I think there's kind of a piece of the jigsaw puzzle missing in Donald Trump where he does not look at women and consider them equal to himself."
Asked by Tapper if Kaine had any evidence of "a pattern of sexual assault," Kaine replied, "My understanding is that there are stories in some papers today with individuals basically saying that they were subject to exactly the treatment that he describes on the tape. So this would be a question for Donald Trump to answer.
"If he says, 'I may have said those things but I never did them,' that's one thing, but I think the tape raises an awful lot of questions, and if you take that tape as Donald is actually describing his actions, then yeah, it is a pattern of assaultive behavior and it's much more than words," Kaine continued.
Since the tape was released on Friday, many GOP leaders and elected officials have rescinded their support for the Republican nominee, with some calling for him to pull out of the race.
"People ought to be asking, 'Do you still think he is qualified to be president of the United States and do you still support him?'" Kaine said about Republicans. "Anyone who has not stated where they are on that question needs to answer."
Clinton has remained mum on the topic since the audiotapes were released. She has been preparing for the debate near her home in Westchester, New York, and has not publicly spoken since the news broke.
Kaine was pressed by Tapper on what Clinton will say about Trump's comments at the debate, but he declined to answer and simply said that Clinton will speak about issues such as the economy and national security.