Texas Trooper Billy Spears was working backstage at SXSW when Snoop Dogg asked to take a photo with him.
A publicist snapped the pic, and Snoop Dogg, the music conference's keynote speaker, posted it and another photo on his Instagram.
But the celebrity photo made its way back to leaders at the Texas Department of Public Safety, who later counseled Spears for behavior that "reflects poorly" on the agency, the trooper's lawyer said.
According to attorney Ty Clevenger, Spears was cited for, in the words of DPS, "deficiencies indicating need for counseling" for appearing with someone with a "well-known criminal background."
The counseling form went into Spears' employee file, but Clevenger said that because it was not considered official department discipline, there was no way to appeal. The note in his file could hurt his chances for promotion, Clevenger asserted.
Clevenger said Spears did not know about Snoop's criminal records, but even if he had, he questioned whether the department would have been as concerned with a photo of a celebrity like Willie Nelson.
"Of course DPS has no policy requiring a criminal background check on everyone who requests a picture with a uniformed trooper," Clevenger said in a blog post. "In fact, DPS has no policy forbidding a photograph with someone who has a criminal conviction."
Snoop Dogg's criminal record includes felony drug possession and possession for sale as well as misdemeanors related to drugs and weapons.
Spears' lawyer also asked if the department's action against the trooper was retaliation for alleging misconduct against a Alcohol and Beverage Control sergeant.
A Department of Public Safety spokesman told the Dallas Morning News that counseling is part of regular supervision and not a type of formal discipline. The spokesman added the department did not comment on personnel matters unless they resulted in discipline.