In the Clinton impeachment we decided that perjury isn't an impeachable offense, at least when it's basically about a president's private life and not the essential parts of his job, treason, murder, rape, subverting democratic elections, corruption ... .
But what about plain old criminal prosecutions? if presidents and candidates don't get prosecuted for obvious perjury either, then that tells everyone else to disregard that lying when testifying it's illegal and dangerous. And it gives lawyers and judges another reason not to believe what anyone says. Testifying to a court -- whether on the witness stand, in a deposition, or a written, notarized affidavit -- is under oath and "under penalty of perjury."
Newsweek has published clear proof that Donald Trump either: (a) lied in a deposition in a case against an ex-employee, about a failed attempt to bribe Florida Gov. Jeb Bush, or (b) lied about it to Bush's face in the second debate. Or both. (Even if bribe is the wrong word, that doesn't affect the specific question that the lie and contradiction were about: Whether Trump was trying to get Bush to reverse his opposition to casino gambling when he hired the Defendant to get Florida to allow him to build a casino and hosted a fundraising event for Bush.)
The lawsuit was in Broward County, Florida. Perjury in a deposition is a third-degree felony under Florida law, and can mean up to five years in prison. I haven't yet found out whether Trump was in Florida or another state when he gave his deposition testimony, and whether that would keep Florida from prosecuting him. But the head prosecutor in Broward County, and/or the county where Trump testified, needs to decide whether to pursue a perjury investigation and prosecution, preferably before the election.