The close relationship with the lawmaker was revealed through emails that were published online last summer after Perceptics was targeted by an anonymous hacker. Colin Strother, a spokesperson for Cuellar, declined to discuss the emails and accused The Intercept of “an agenda and a bias.” Perceptics declined to comment.

Perceptics, a company that sells cameras that scan license plates, has frequently tapped Cuellar for favors since at least 2011, including a push to edge out a competing vendor, using its team of lobbyists and campaign contributions to curry favor with his office.

The lawmaker has defended his record as part of his duty as a border lawmaker focused on national security, but emails show Cuellar acting at the behest of well-connected lobbyists for a government contractor.

Rep. Henry Cuellar, a conservative Texas Democrat, has used his perch in Congress to push for funds for private prisons , drone surveillance , and increased border security enforcement .

The emails show the lawmaker’s name mentioned dozens of times as an ally Perceptics could use to sponsor legislation or write official letters on the company’s behalf. Lobbyists and executives at the firm referenced him as Perceptics’s “friendly congressman” and “our Cuellar firepower.”

Cuellar’s close ties to business interests stand out, even among other conservative House Democrats. Cuellar is the biggest Democratic recipient of campaign donations from the private prison industry, one of the only Democrats vote to delay regulations on payday lending, and has voted in support of the Trump administration’s agenda in Congress a record 75 percent of the time.

The lawmaker’s unusually conservative record has attracted a progressive primary opposition from Jessica Cisneros, an immigration attorney. The Texas primary is on Super Tuesday, March 3. The primary has attracted heavy levels of spending from progressive and business interests, with a political action committee associated with border security lobbyists raising thousands in support of Cuellar.

The relationship began in earnest in early 2011 after Cuellar, who has been in office since 2005, was appointed to the House Homeland Security Committee’s panel overseeing border security. “And here are the D’s….note Cuellar!” wrote Cristina Antelo, a contract lobbyist, passing along a press release announcing the lawmaker’s new committee assignments.

John Dalton, the chief executive of the company, was reminded in a follow-up email from Antelo that she had introduced him to Cuellar “at least twice, once at a fundraiser I hosted for the CHC BOLD PAC,” a reference to the Congressional Hispanic Caucus’s PAC. Antelo, notably, serves on the board of CHC’s foundation and has routinely hosted CHC BOLD PAC fundraisers over the last decade.

In 2011, Perceptics pushed to initiate an inspector general investigation against Axiompass, a competing firm that had been awarded a contract by the State Department to install vehicle identification technology along the U.S.-Mexico border. Executives at Perceptics believed that they had been unfairly passed over for the lucrative deal.

Cuellar stepped up to the task. The Texas lawmaker contacted State Department Inspector General Steve Linick on March 22, 2012, requesting an investigation over the agency’s procurement process.

One year later, Patricia Inglima, an aide to Cuellar, passed along a letter from the State Department to Perceptics’s team, confirming that her office had successfully encouraged the agency to open an inquiry. “I have just confirmed with OIG that the letter is in reference to the license plate reader technology bid and that the investigation is continuing,” Inglima wrote.

In 2014, the Podesta Group, a now-shuttered lobbying firm that once managed Perceptics’s lobbying efforts, boasted in a client report about overseeing a sophisticated effort to undermine the Axiompass contract. “Together, we successfully recruited allies in Congress who demanded that the State Department launch an investigation,” the report noted, offering further plans for tying funding for the contract to the results of the investigation.

During the following sessions of Congress, Perceptics lobbyists assisted Cuellar in privately urging then-Rep. Kay Granger, R-Texas, a senior lawmaker on the Appropriations Committee, to increase spending on U.S.-Mexico foreign aid designed to boost border vehicle tracking technology.

The plan was detailed in a document summarizing a call with Perceptics’s lobbying team. “Cristina sent the latest draft of our proposal for the Economic Support Fund for Mexico to a contact on Rep. Cuellar’s staff,” the document noted. The team also discussed a meeting between Mexico’s ambassador to the U.S. and Cuellar, to which “Perceptics would be invited.”

After a series of meetings between Perceptics and the lawmaker, Cuellar wrote a letter to Granger urging her to adopt $135 million in foreign aid into the following budget for the construction of specialized cargo traffic lanes enhanced with nonintrusive automated vehicle identification technology, a system Perceptics sold to the government.

Dennis Thompson, a program manager at Perceptics, emailed his team to note that “Cuellar personally and Cuellar’s staff have said that in conversations with Chair Granger and her office, LPRs were discussed specifically under the category of non-intrusive inspection technologies.”