Sandeep Dhaliwal, 42, was the Harris County Sheriff's first-ever Sikh Deputy and had been pushing for a historic expansion of religious rights in the department, reports The Houston Chronicle newspaper.
Dhaliwal pulled over a vehicle around 12.45 p.m. on Friday in the 14800 block of Willancy Court in the Cypress area, Harris County Sheriff's Office Maj. Mike Lee told reporters here.
According to Lee, dashcam video showed that Dhaliwal and the suspect, Robert Solis, 47, still in his car, having a conversation with no sign of confrontation.
A few seconds after Dhaliwal returned to his squad car, the suspect ran up and shot him in the head multiple times, Lee said. Dhaliwal was airlifted to the hospital, where he died.
Solis was charged late Friday with capital murder in the case, The Houston Chronicle reported.
A woman who was outside gardening heard the shot and saw Solis run to a getaway car.
Lee said the suspect then went to a store nearby. After a brief search, authorities detained Solis, who has a criminal record that includes convictions for aggravated assault with a deadly weapon, aggravated kidnapping and driving while intoxicated.
Dhaliwal was the county's first Sikh deputy when he joined the force 10 years ago, and became a national figure after convincing the department to allow him to wear religious attire and grow a beard while on patrol.
"He was a hero, a trailblazer," Sheriff Ed Gonzalez said of Dhaliwal, who he considered a close friend. "There are no words to speak to how heartbroken we are, how devastated."
Dhaliwal, a father of three young children, began his career in law enforcement out of a desire to serve after then-Sheriff Adrian Garcia reached out to strengthen the department's relationship with the Sikh community after deputies botched a domestic violence call at a Sikh family's home.
He was also very active at his Gurudwara, and his house of worship held a special ceremony after he became a Deputy.
"He was very, very, very important," community member Sampuran Singh said. "He was always willing to do what the community needed him to do."
( With inputs from IANS )