Do Trial Lawyers give opening statements under oath?

I'M the plaintiff in a upcoming civil trial v ex-employer. Defense lawyer say its frivolous, he claims I'M trying to extort money from my old employer. he claims I made 2 other attempts 1-Unemployment benefits 2. U.S. Dept of Labor wage/hour (USDOL) and says I lost both. truth is #1. My State unemployment division will verify, I appealed the local denial of benefits, and our State's 3 panel Unemployment appeals judges reversed that and I got full benefits charged to the defendant's and # 2. I filed a USDOL claim in 2003, a few days before I was fired. They audited the business and ended 3 yrs later, Me and 65 others all got paid, money we'd been cheated of. Although due to what the investigator (USDOL) called a "Time Bar" i only got a portion of what i was owed. The U.S. Dept of Labor has verified they closed the case and collected for us. Plus, I have a 2007 IRS W-2 tax form from the company (Defendant) show that they paid me 4 yrs AFTER i was fired. I can prove the Lawyer statements are 100% false. Will that simply hurt his credibility or could he face some sanction or perjury? are lawyers statements in court filings under oath or not?