Democratic lawmakers on Wednesday condemned the Justice Department’s handling of a landmark tobacco lawsuit and formally asked for an internal investigation to see whether political appointees with ties to the tobacco industry improperly influenced the case.

In letters to Justice Department Inspector General Glenn Fine, Democratic Senators and House Members said that the Justice Department’s decision to ask for only a $10 billion penalty against tobacco companies accused of conspiracy and racketeering — rather than the $130 billion penalty the government’s own expert recommended — smacks of a political decision that would effectively shield tobacco companies from having to make 25 years of payments for smoking cessation programs.

“It reeks of political interference … from a White House that chooses its industry friends over the well-being of our nation’s kids,” said Sen. Frank Lautenberg (D-N.J.). The Senate letter was signed by Lautenberg, Sens. Edward Kennedy (D-Mass.), Dick Durbin (D-Ill.), Tom Harkin (D-Iowa), Bill Nelson (D-Fla.) and Ron Wyden (D-Ore.).

The signers said they were determined to get to the bottom of why the Justice Department appeared to undermine its own case.

“I find it hard to believe that this is an innocent mistake. We’re going to dig here,” said Wyden. “The Justice Department owes the American people some answers.”

In the meantime, Rep. Henry Waxman (D-Calif.) and Marty Meehan (D-Mass.) noted in their separate letter to Fine that both The Washington Post and the Los Angeles Times cited anonymous sources as saying that career lawyers at the Justice Department had pushed for the $130 billion penalty, while political appointees — in particular former tobacco company lawyer and current Associate Attorney General Robert McCallum — had insisted on dropping the requested penalty down to $10 billion.

“The Justice Department’s approach to tobacco litigation should be based on the facts of the case and not political favors to the tobacco industry,” Waxman and Meehan wrote. “It is highly unusual for government prosecutors to abandon evidence-based testimony by their key witnesses at the last moment in a major trial. It is even more unusual for changes in strategy to be dictated by a political appointee with clear ties to the industry that is the defendant in the case.”

Both the House and Senate letters request that Fine determine whether McCallum or any other politically appointed Justice official improperly influenced the case.

The Justice Department was expected to release a statement on Wednesday evening that sought to clarify the department’s reasons for asking for a reduced penalty. However, the statement was not made available by press time.

While Democrats wasted no time getting out in front of the issue, tobacco industry foes in the GOP were mum regarding the Justice Department’s handling of the case.

“I’m going to read [the news stories] and look at it, but I don’t have an opinion yet,” said Sen. Mike DeWine (R-Ohio) who has long pushed for Food and Drug Administration regulation of tobacco products.

Still, Lautenberg said he expected Republican support for demanding an explanation from the Justice Department.

During the eight-month trial, tobacco companies were accused of conspiring to illegally target minors and suppress evidence showing the dangers of smoking cigarettes. Government witness Michael Fiore testified that a comprehensive smoking cessation program aimed nationally would cost $5.2 billion per year and that 25 years of funding would be needed to ensure its success.

But when government lawyers wrapped up their case on Tuesday, they only requested a penalty of $10 billion, enough to cover a five-year smoking cessation program.

In the next few months, U.S. District Judge Gladys Kessler is expected to decide whether the tobacco companies are culpable and, if so, how big any penalty should be.

Still, Kennedy suggested that the Justice Department has enough time to revise its request for monetary penalties via a post-trial brief.

“There are legal procedures by which they can reverse themselves, and we’re asking them to do that,” he said.