Why does Harvey Specter tell Donna that finding an allegedly buried document will help the case?

Question

In Season 2 episode "Break Point", Donna found that she signed in an allegedly buried document and then lost it, when Harvey knows that Donna found the document he react pretty "normal", telling that the appearance of that document will help the case...

How is that going to help the case?

• For me it will look like the firm (Donna or Harvey) did buried the document.
• If that help someone is to Harvey's cause not Donna's, as he can state that Donna did a mistake or buried the document without Harvey's consent.
• As is known in later episodes hardman planted this document, If finding the document help the case.. then why planted in the first place to be found afterwards?

Or maybe I'm missing something else or legal hole... Im not an expert just trying to understand the logical explanation of the argument

Answer 1

If they had document and they buried it, it would be perjury, in which case the opposition would have the upper hand if they found out that Harvey and Donna perjured themselves.

Donna knows that she did not receive the document, so she initially told Harvey that the document must have never arrived. In later episodes, Donna found the document with her name on it. She freaked out and buried it with out telling Harvey about it. Now, Hardman knows that the document is in the firm (since he planted it). So if Harvey denies of having that document, it would be perjury.