|US protected drug smuggler, BBC video|
The wedding was part of a "Door of Hope" event which allows meetings between people not allowed to cross.
The BBC and other media reported on the unusual wedding.
Joshua Wilson, from an organisation representing border guards in San Diego, told the San Diego Union-Tribune that agents were "upset".
"They feel like they were taken advantage of, feel like they were duped," he said. "Turns out we provided armed security for a cartel wedding."
The incident may put the annual event on jeopardy.
Houston, who is from San Diego, signed official Mexican documents with Evelia Reyes of Mexico, making them husband and wife.
"It's a statement that love has no borders," Houston said afterwards.
He had been arrested in February  at another border crossing after police found 19.5kg (43lb) of heroin, 21kg [47 lb] of methamphetamine and 19.5kg [43 lb] of cocaine in his car, according to the complaint.
However, he was released on bail with a ban on leaving the US after he pleaded guilty in court in May. His sentencing is in February.
A Border Patrol spokesman, Takae Michael, said Houston had been screened through an internal vetting process based on information provided by the event's organisers, the Border Angels group, and no criminal activity had shown up.
Nor were his plans for the wedding reported to the Border Guard in advance.
"They showed up dressed for a wedding," Mr Wilson said. "The agents there were powerless to stop it. We were certainly put on the spot."
The annual meetings on the border between San Diego and Tijuana started in 2013.
Enrique Morones, executive director of Border Angels, said his organisation had never done "any background checks as the Border Patrol advised us they will do all background checks and advise us which families have been cleared"."
12/21/2017, "Border groom passes federal background check, turns out to be convicted drug smuggler," San Diego Union-Tribune, Kristina Davis
|US-Mexico border, U-T video|
Houston, a U.S. citizen, is awaiting sentencing in San Diego federal court on a drug smuggling conviction
— a fact that the Border Patrol says it did not know when it ran a background check on him clearing him to participate in the event at Border Field State Park.
Houston was arrested in February as he crossed through the San Ysidro Port of Entry. Found hidden in his Volkswagen Jetta were 43 pounds of heroin, 47 pounds of methamphetamine and 43 pounds of cocaine, according to the complaint.
“The agents are upset, feel like they were taken advantage of, feel like they were duped,” said Joshua Wilson, vice president and spokesman for the National Border Patrol Council Local 1613.
“Turns out we provided armed security for a cartel wedding.”
The incident could put future “Door of Hope” events in jeopardy.
The event is closely monitored and choreographed, with a handful of vetted families on the U.S. side allowed to embrace and greet family members on the Mexican side in three-minute reunions under the watchful eye of Border Patrol agents. The encounters are held in a small strip of land owned by the Department of Homeland Security known as Friendship Park.
The enormous border gate has opened with fanfare like this six times since 2013.
The events are organized by the Border Angels nonprofit group, run by executive director Enrique Morones. He gives questionnaires to interested families who cannot cross the border legally for whatever reason, and the forms are then provided to the Border Patrol for approval.
“Border Angels has never done any background checks, as the Border Patrol advised us they will do all background checks and advise us which families have been cleared,” Morones said in a statement Wednesday.
Twelve families were approved for the Nov. 18 opening — including Houston — although one family did not show, Morones said.
Border Patrol spokesperson Takae Michael said Houston was “screened through an internal vetting process based on biographical information provided to us” by Morones. “A review of the provided information, through our DHS systems, did not indicate criminal activity,” Michael said.
The wedding between Houston and Evelia Reyes was a surprise to agents. The couple — in only a few minutes — signed documents from the Tijuana municipal authorities, posed for pictures and hugged. The nuptials were widely covered by news outlets on both sides of the border, including the Union-Tribune.
“It's a statement that love has no borders,” Houston told reporters at the time. “Even though we are divided by a giant fence here, we can still love each other on both sides of the fence.”
He said his wife was working with an immigration attorney to get a green card to live in the U.S.
Wilson, the Border Patrol union rep, said Morones should have alerted the agents to the wedding.
“They showed up dressed for a wedding,” Wilson said. “The agents there were powerless to stop it. We were certainly put on the spot.”
The Border Patrol said that after the wedding, “a subsequent review of Houston’s information was completed and confirmed a match for a previous arrest for drug smuggling.”
Morones said he plans to meet soon with San Diego’s new Border Patrol Chief Rodney Scott to discuss the incident and future events.
“We were shocked to learn this past week of Brian Houston’s very serious criminal situation. That goes against everything Border Angels stands for,” Morones said. Border Angels is a humanitarian group serving immigrants that started decades ago by leaving water and other supplies in the desert for border crossers.
Houston, a SENTRI pass holder, approached the port of entry at 10:30 a.m. on Feb. 28 and said he had nothing to declare, according to the complaint. But the U.S. Customs and Border Protection officer smelled a strong chemical odor while inspecting the trunk and noticed scrapes that suggested the lining of the compartment had been tampered with, the complaint states.
Under the lining, several plastic-wrapped packages could be seen, the complaint says. The car was driven through an X-ray machine and several more packages were detected in all four doors, rear quarter panels and the spare tire. There were 67 packages in all.
After his arrest he was granted release on $20,000 bond secured by the signatures of his parents and a 15 percent cash deposit, according to court records. He was also not allowed to enter Mexico and had to surrender his U.S. passport.
He pleaded guilty in May to importing the three drugs. Sentencing is set for Feb. 23."