Thousands of mourners attended an emotional memorial service Thursday for Kaufman County District Attorney Mike McLelland and his wife, Cynthia.
Gov. Rick Perry and law enforcement officials from around the state joined family and friends of the couple, who were found shot to death in their home Saturday.
The killings came just two months after the unsolved shooting death of Assistant Kaufman County District Attorney Mark Hasse.
Perry said the McLellands' life of service had saved other families from the grief being felt by their survivors now.
"We cannot waver in our determination and dedication to the law, and we can not diminish our resolve to find the evil doers in society and put them where they can no longer do harm," he said.
Kaufman County District Attorney investigator Chris Bryant was among the people close to the couple to speak at the service.
"From our first meetings to the last day of their life, our happiest moments were in their company," Bryant said.
Mike McLelland's, stepdaughter Christine Foreman, echoed the governor's thoughts.
"We can't let the fear of what people are going to do to us stop us from doing the right thing," she said. "The right thing is never easy. It's hard, and he knew that and he stood up anyway."
Mike McLelland served in the U.S. Army and as a public defender before being elected Kaufman County district attorney in 2010.
His wife was a nurse, and both had worked as clinical psychologists in the past.
"As hard as it is to loose these two people, knowing they left together gives us and their family a sense of peace," family friend Leah Phillips said.
A visitation for the couple will be held Thursday night, with a funeral and burial to follow Friday, in Mike McLelland's hometown of Wortham.
A McLelland family representative gave the following statement to NBC's Today show:
"On behalf of the McLelland family, we would like to thank everyone for all of the thoughts and prayers for our family during this tragic time. We would greatly appreciate the continued support for our family while we grieve the loss of these two special people. We sincerely appreciate the efforts of each and every law enforcement agency that is so diligently working on this case. We respectfully request that all news and media outlets respect our privacy as we grieve our loss."
Honor Guard organizer Chris Heisler said he regularly speaks with the family.
"They're heartbroken, and they're angry. This is something that happened here in North Texas. It's impacted them, and also citizens and communities around the country," Heisler said.
Authorities are forming theories related to the death of the district attorney and his wife. Both were found shot to death Saturday in their house near Forney, about 20 miles east of Dallas.
Authorities do not have a suspect in custody and are not ruling any possibility out. No arrests have been made and no suspects have been named.
Some investigators that spoke to NBC 5 are downplaying earlier theories of a connection between the killings and the Aryan Brotherhood gang. One theory believes the suspect could be described as a "lone wolf" with a "grudge" against the their victims.
NBC 5's Jeff Smith and Scott Gordon contributed to this report.