On this weekend’s broadcast of “Fox News Sunday,” chief strategist for Democratic presidential nominee Hillary Clinton Joel Benenson said it is “fairly routine,” that Clinton’s former chief of staff Cheryl Mills was given immunity in the FBI’s investigation into Clinton use of a private unsecured email server during her tenure as secretary of state.

Partial transcript as follows:

WALLACE: We learned on Friday that as part of the FBI investigation into Hillary Clinton’s private e-mail system that Cheryl Mills, her chief of staff when Clinton was secretary of state, that she was one of the people, five people, who received limited immunity. How do you explain that, Joel?

BENENSON: Well, Chris, I think you’re probably familiar with what limited immunity is. It’s fairly routine when police and law enforcement are investigating a particular issue and you’re sitting down with them to give fool cooperation, turn over materials, hand over computers, blackberries, whatever. They narrow their scope of their investigation to the issue at hand. So a limited immunity is anything else is irrelevant to them at that. They’re looking at the specific investigation. And that’s what limited immunity means, Chris. I believe you know that. so it’s fairly appropriate and routine when people are sitting down with them, turning over a wealth of materials that have nothing to do with the investigation at hand.

WALLACE: Well, it had something to do with the investigation. they wanted the laptop for a reason. If I may just asked question. if Clinton —

BENENSON: No no

WALLACE: Well, I’m trying to ask a question, Joel.

BENENSON: Yeah

WALLACE: If Clinton did nothing wrong, if no one on her staff did anything wrong, why did Cheryl Mills ask for and receive immunity, limited immunity from criminal prosecution in this case?

BENENSON: Because the reason for that, Chris, is to that if you’re handing over a vast amount of materials, something like your computer or your blackberry or whatever, files that they want that are not germane or relevant. It could be conversations with anybody else, your accountant, somebody. law enforcement offers this up to you to encourage you to sit down and provide

WALLACE: Well, they didn’t offer it to her. Cheryl Mills asked for it.

BENENSON: But it’s a fairly routine process, and you know that, Chris. Let’s talk about it. You know that prosecutors and investigators, when they’re investigating —

WALLACE: I’ll be honest. i don’t know that.

BENENSON: Can I finish the answer …they wanted to be sure they had access to Cheryl Mills emails nothing else.