Sue Dixon often warns her high school grandson never to sign online petitions and to be suspicious of all websites asking for personal information.

Now Dixon, a public school teacher in Gatesville, wonders whether she’s the victim of some sort of web-related scam.

“Absolutely not,” Dixon said when asked whether she recently entered her name, email address and mailing address into an online form asking her state representative to support the use of public dollars to fund private education. “No, no, no, no, no.”

The school choice group responsible for sending out more than 17,000 of these letters to legislators in the last few months begs to differ. “Constituent letters sent to legislators are credible and uniquely verifiable,” according to a statement from John Colyandro, president of Texans for Education Opportunity, a new organization pushing for private school tuition subsidies this session.

A letter purportedly sent from Dixon went to state Rep. J.D. Sheffield last month. It was one of thousands that deluged the district offices of Sheffield, R-Gatesville, and other lawmakers representing mostly rural parts of Texas in recent weeks — stirring confusion and suspicion after the lawmakers said they struggled to find any constituents who recalled adding their name to such correspondence.

“Some of these people we knew were pro-public education and not pro-voucher,” said Sheffield, who received 560 letters, all postmarked from Austin. “One of them was my neighbor.”

Private school choice is one of the big issues dividing the House and Senate this legislative session. The Senate Education Committee on Thursday passed Senate Bill 3, which would create an education savings account program in Texas. But the House is unlikely to take up the bill for a vote, even if it's approved by the full Senate.

Texans for Education Opportunity said it generated the torrent of letters through an online ad campaign targeting constituents of 32 legislators, including three Republican senators who have not supported similar proposals in the past. The organization is lobbying the Legislature to back education savings accounts, which would give parents state dollars to pay for private school tuition and homeschooling.

On Wednesday, the group said the letters are legitimate and proclaimed its campaign — “conducted with utmost integrity and respect for the millions of voters” — a success.

“The support for school choice is broad and bipartisan, and we remain optimistic that school choice will get a fair hearing and vote this session," Colyandro's statement said.

The group’s representatives declined several requests for on-the-record interviews, but it forwarded questions to its advertising vendor, LCX Digital.

The advocacy group, however, shared with The Texas Tribune a spreadsheet that it said contained information on 17,017 constituents who responded to the ad campaign, resulting in letters in their names being sent to their local representatives. That data, which showed that each lawmaker received more than 500 letters, prompted a flurry of new questions.

Why, for instance, does the spreadsheet list an email address for Dixon that she doesn't recognize? Why does the data list Dixon as “Anita,” her legal name, when she always goes by Sue? And why does a Google search suggest the email address belongs to another Anita Dixon in North Carolina? (Several calls to listings for that Anita Dixon went unanswered, or were disconnected phone numbers.)

Former state Rep. Rick Hardcastle also has been scratching his head after his name was attached to a pro-school choice letter sent to Rep. Drew Springer, R-Muenster, who filled Hardcastle’s House seat six years ago. The former lawmaker, who said he doesn’t “believe in vouchers of any kind,” does not recall filling out anything from the advocacy group. And he doesn’t recognize the email address listed by his name in the group's database.

Hardcastle met with representatives of the school choice group this week but still doesn’t know why his name emerged in the campaign.

“It’s probably a whole new example of bullshit that legislators have to put up with,” he said. “It gives you one more thing to worry about in the electronic age.”

Tim Browning, of LCX Digital, said he could not immediately answer questions about Dixon and Hardcastle's data, which fill out just two rows in a massive data set.

“Any explanation for why this might happen would be flawed because I would have to make assumptions I couldn’t 100 percent know to be true,” he said in an email. “I am 100 percent certain that the individuals in those districts were targeted with digital education ads. People who clicked on the education ad were then re-targeted with a different ad that allowed them to send a letter to their representative.”

But lawmakers say they’ve struggled to find confirmation that constituents authored the letters, and they would be surprised if so many folks in their mostly rural districts backed school choice policy anyhow.

A University of Texas/Texas Tribune Internet survey of 1,200 registered voters showed a lack of support for “private school choice” statewide, with 35 percent of those surveyed supporting it. Suburban and rural voters were less likely than urban voters to support it.

Springer said he wasn’t sure what to think when the mysterious letters poured into his district office from mid-February to mid-March. He said he's since called more than two dozen alleged letter writers, but can’t find anyone who recalls doing so.

“I don’t have anyone who is pushing this,” he said.

Sen. Kel Seliger, R-Amarillo, said his office made a handful of calls to constituents but didn’t find anyone who would confirm sending one of the 544 letters he received. Through that sleuthing, however, he said he learned that one of the letters was supposedly from a constituent who had died in June.

“The credibility is very strained,” he said about the letter-writing campaign.

Rep. Travis Clardy, who received 535 letters at his Nacogdoches office, said it could damage his own relationship with constituents if some of the letters are ultimately found to be dubious.

“Then all of a sudden we couldn’t count on constituent feedback,” he said. “If you’re going to play the game, you need to be upfront about who you are and who you represent.”

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