The couple was headed to see Tamishia Moats' dying mother when an officer pulled their vehicle over for rolling through a red light, The Dallas Morning News reported Friday.
"He was pointing a gun at me as soon as I got out of the car," Tamishia Moats told the newspaper.
Officer Robert Powell spent about 13 minutes writing Moats a ticket and threatening him with arrest while his wife went into the hospital. By the time Moats got inside, his mother-in-law had died.
Dallas Police Chief David Kunkle says Powell should have offered to help the couple once he was told what was happening.
"His behavior, in my opinion, did not exhibit common sense, the discretion, the compassion that we expect our officers to exhibit," said Kunkle.
The ticket issued to Moats has been dismissed, a police spokesman told the Morning News.