I am an HR Manager and worked for my employer for 25 years, 11 months in good standing. I conducted a harassment investigation on sr. mgt

You could have a retaliation case against your employer if you can show that you conducted a competent investigation and the facts that you uncovered that were unfavorable to your manager would lead a reasonable HR professional to conclude that the employer had acted illegally, and that you reported this finding to your employer and recommended that it take action to correct the illegal situation.  This would be "oppositional" protected activity under Title VII (assuming the claim was harassment because of the victim's federally-protected status).  Michael Caldwell 404-979-3150