But to Brown, a state senator and the 2008 Republican nominee for governor of Montana, the philosophy aligns perfectly with conservative ideology. He's one of the more high-profile figures reaching out to other social and fiscal conservatives, hoping to create a bipartisan movement against capital punishment.
"I believe that life is precious from the womb to a natural death," Brown said.
The Roman Catholic church has long been an organized and vocal critic of the death penalty, but the new effort is trying to bring in other conservatives shaped by both evangelical faiths and political ideology.
Now, liberals and conservatives - longtime opponents on contentious social issues from abortion to capital punishment - are working together in a time of strong political polarization.
The effort took center stage at the National Coalition to Abolish the Death Penalty's annual conference over the weekend in Louisville. Brown was joined by a conservative minister, the Rev. Matt Randles of Headwaters Coventant Church in Helena, Mont., and Heather Hass, a former National Republican Congressional Committee staffer. They walked fellow activists through how to make their case to others about the anti-death penalty movement.
Shari Silberstein, executive director of Equal Justice USA, a Brooklyn, N.Y.-based anti-death penalty organization, said working with conservatives is about common sense and common ground.
"It's not really an ideological question," Silberstein said.
The effort has been backed by Richard Viguerie, a fundraiser and activist considered the father of the modern conservative movement. Viguerie, in a July 2009 essay in Sojourners magazine, wrote that executions are supposed to take the life of the guilty - but noted there are enough flaws in the system to fear an innocent person has been put to death.
Viguerie noted that death row inmates have been exonerated by DNA evidence, raising the prospect that prosecutors and juries made mistakes in cases without scientific evidence and in cases that predate the science.
"To conservatives, that should be deemed as immoral as abortion," Viguerie wrote.
And as lawmakers continue to slash budgets because of the slumping economy, many are wondering whether the price tag of the death penalty and the resulting drawn-out legal process is worthwhile. The winding series of appeals often runs up huge legal bills for states, which many advocates say is often more expensive than the cost of life imprisonment.
In 2007, New Jersey and New Mexico became the 14th and 15th states to abolish the death penalty. Ten other states have considered repealing it in recent years.
Kansas lawmakers have four days of hearings scheduled later this month to consider abolishing executions in the state, based in part on cost. And a Duke University professor concluded that North Carolina could save $11 million a year if it halted the death penalty.
"Criminals should be prosecuted," Brown said. "I want it to be life without parole. In the long run, that's much cheaper."
Not all conservatives are open to Brown's pitch. Kent Scheidegger, legal director of the Criminal Justice Legal Foundation and an outspoken capital punishment supporter, said most of the costs of a death penalty case come from "exhaustive investigation" of the defendant's background and should be cut out.
"I think those who are falling for this line are misguided," Scheidegger said. "The death penalty does not need to cost more than life imprisonment."
While there are no hard numbers on how many conservatives have joined the anti-capital punishment campaign, those involved say it's a growing movement.
"I am so sick of American polarizing politics," said Laura Porter, director of organizing for the Equal Justice USA. "I think we all have a lot more in common than is ever acknowledged."
Brown knows not everyone will agree with him, but he and other death penalty opponents are willing to take small gains.
"There are some people I'm not going to convince," Brown said. "That's all right. I'm not trying to win over the world."