Updated 10/24/17 at 11 a.m. with a statement from the U.S. attorney

Updated 10/13/17 at 5 pm with a statement from TxDOT

A second Dallas real estate man was sentenced Friday to federal prison for a land-flipping scheme using inside help from the Texas Department of Transportation to profit from selling tracts along Interstate 35E .

Kevin Bollman, 49, will spend 15 months in prison under an agreement with the U.S. attorney's office for defrauding TxDOT out of $12.9 million.

Bollman also was ordered to pay $1.5 million in restitution to TxDOT.

Last month, Bollman's partner in the Denton County land deals, Wade Blackburn, 35, was sentenced to one year and one day in prison and ordered to pay $1 million in restitution.

Like in Blackburn's case, Bollman could have gotten more prison time due to the size of that dollar figure. But Assistant U.S. Attorney Christopher Eason said the case will serve as a deterrent to other real estate speculators who are thinking about cheating to make a buck. The message, he said, is that you will go to prison and be a felon.

"They're on notice now," Eason told U.S. District Judge Marcia A. Crone.

Bollman did not address the judge during the brief hearing. His attorney, Michael Gibson, declined to comment.

Eason also said it's the first time in recent memory that TxDOT is getting money back for a fraud committed against the agency. He said TxDOT approved of the sentences.

"We are thankful that federal prosecutors and the FBI were successful in this case, where the defendants defrauded the state of Texas," said TxDOT spokesman Tony Hartzel. "We are glad this case has reached its logical conclusion."

Both men pleaded guilty earlier this year to conspiracy to commit mail fraud in connection with the land deals.

Kevin Bollman (background) leaves the courthouse behind his attorney, Michael Gibson, after Friday's sentencing hearing in Plano. (Jae S. Lee / Staff Photographer)

Crone told Bollman to report to the Bureau of Prisons on Nov. 27 to begin his sentence.

The former TxDOT right of way supervisor who made it happen has not been charged.

Acting U.S. Attorney Britt Featherston issued a statement in response to questions from The Dallas Morning News about why the former public official, who is referred to as an "unindicted co-conspirator," wasn't prosecuted.

"The evidence uncovered in this investigation revealed who the culprits were in this conspiracy.," he said. "They were charged, indicted, and have now pleaded guilty, based upon all of the evidence."

The 2016 indictment against Bollman and Blackburn said the men bought land cheap alongside I-35E and then flipped it to the state at inflated prices after lying about bogus development plans that they claimed would be ruined by the planned highway expansion. Land under development qualifies for higher compensation.

The Dallas Morning News first wrote about the scheme in 2013.

Prosecutors said the men raised investment money to buy right of way along I-35E and then flip the land to TxDOT between 2008 and 2011. Officials said the deals involved six parcels, totaling more than 25 acres, which were sold in four transactions.

The 24-page indictment mentions a 2008 email that Blackburn sent to Bollman about a site plan for some of their highway property.

"This is obviously just for TxDOT justification," Blackburn said in the email. "Notice how I am having the architect say that most of the property will not be developable after the take."

Wade Blackburn (right) left the federal courthouse in Plano after his sentencing hearing on Sept. 14.He pleaded guilty in April to one count of conspiracy to commit mail fraud in connection with the land deals with the Texas Department of Transportation in Denton County. (Jae S. Lee / Staff Photographer)

The Dallas real estate investors received "preferential treatment" from TxDOT in being able to sell their land to the state first, using option contracts, federal authorities said.

Former U.S. Attorney Malcolm Bales of the Eastern District of Texas said last year that Blackburn and Bollman developed a cozy relationship with the former TxDOT right-of-way supervisor to pull off their scam.

The indictment refers to him as an "unindicted co-conspirator."

Bollman and Blackburn paid the alleged co-conspirator more than $446,000 and hired his son, the indictment said.

And in December 2011, Bollman and Blackburn spent about $15,000 on a hunting trip they took with the alleged co-conspirator, as well as a Denton County transportation consultant and others, according to the indictment.

Blackburn's plea documents said he told his investors he had a "connection" with a TxDOT employee who would help set up the option payments.