A private investigator is asking the U.S. Supreme Court to reverse a decision by the Maine Department of Public Safety denying him a license to practice his profession because he criticized a Maine State Police officer’s conduct in a fatal shooting. The investigator, Joshua Gray, claims that the denial of license constitutes a violation of his right to free speech under the First Amendment, according to his attorneys at the Institute for Justice (IJ), a public interest law firm with a special interest in occupational licensing issues. “When the government retaliates against people because of their speech, it violates the First Amendment,” IJ senior attorney and lead counsel Paul Sherman said in a statement. “That’s true whether the government is imposing a fine, withholding a parade permit, or denying an occupational license.” The petition for review in Gray v. Maine Department of Public Safety, court file 21-375 (pdf), was filed …