technology, get it right, so that there's no suspicion about what agenda anyone may have. >> reporter: irs commissioner is due to testify before the house ways and means committee friday. and house oversight on monday on the missing e-mail matter. >> all i can say is, it looks to me that this may be a cover-up. >> reporter: utah republican orrin hatch and john wyden are leading the investigation in the senate finance committee targeting conservative groups. in the meeting with the senators this week, hatch said he didn't mention e-mails of six other irs officials are also missing, but did say lerner's hard drive had been destroyed. >> not only did it crash, but they said they no longer have it. so it wasn't recycled, they just got rid of it. >> reporter: i.t. experts said the irs uses exchange for e-mails. e-mail enters and leaves the irs, it would all pass through and be saved on these exchange