A 25-year veteran of the commonwealth’s attorney’s office is facing off against a criminal defense lawyer in Arlington County’s race for top prosecutor in the Aug. 23 Democratic primary.

Theo Stamos, 53, chief deputy commonwealth’s attorney in Arlington, is the front-runner to succeed Arlington County Commonwealth’s Attorney Richard E. Trodden.

Her opponent, David W. Deane, 39, is a native Virginian who has been practicing law for 14 years. He is a partner at Albo & Oblon in Arlington, where he manages the firm’s criminal division and started his career as a prosecutor in Fairfax County before going into private practice.

Stamos says her experience should win her the position, while Deane says he will bring a fresh perspective to the office. Outside of modest operational changes, the office’s structure would remain the same under Stamos. Deane wants to streamline the way the office handles drug charges and hire more Spanish-speaking prosecutors, a move Stamos also welcomes.

When it comes to the death penalty, the two candidates differ.

Deane opposes capital punishment and said: “The commonwealth’s attorney has the discretion of what level of charge to bring. I think the only valid argument for the death penalty is sheer vengeance.”

Stamos said it is her job to present the facts of a capital case to the jury.

“These are the kinds of cases where the jury has to make that determination, and I think it is appropriate for them to do so,” she said.

Stamos, who grew up in Chicago and worked as a journalist while going to law school at night, has received numerous endorsements in Arlington and throughout Virginia. She significantly outraised Deane; about $99,100 as of June 30, compared with Deane’s $7,880.

“I believe very deeply in the criminal justice system we have in this county and making it work the right way,” said Stamos, who added that she is honored to be a public servant.

Among the highlights of her career, Stamos won five life sentences plus 168 years in prison in 2010 for Jorge Avila Torrez, who was found guilty of abducting and raping a University of Maryland graduate student, among other charges. Torrez, a former U.S. Marine, was indicted by a federal grand jury in May for the 2009 slaying of Navy Petty Officer Amanda Jean Snell, 20, at Joint Base Myer-Henderson Hall.

Stamos also worked to convict several murderers. Among them was Matthew J. Pahno in 2006, who was convicted of strangling and decapitating his aunt, Maria “Marissa” Teresa Dela Cruz Escoto, and Zachary Cooper, who was convicted of killing his wife, his 5-year-old daughter and his girlfriend in 2002.

“The hallmark of this job is having the seriousness of purpose, understanding and appreciating prosecutorial discretion and showing how it is exercised,” Stamos said. “I think my experience doing what I do, being a mom, a parent in the community, is what I need to do this job well,” she said.

S. Randolph Sengel, Alexandria commonwealth’s attorney, endorsed Stamos and said she is a skilled trial attorney with “excellent judgment in terms of assessing cases and determining what the right outcome is.” He said experience is key.

“If you are out there picking a doctor or some other specialist, you really want someone who knows what they are doing,” Sengel said.

Trodden agreed.

“She has a wealth of experience,” said Trodden, who has been commonwealth’s attorney since 1993. “She has tried the big cases. She has got judgment, and she has a human touch.”

Deane argued that Stamos’s professional career has been in the same office. He can offer a fresh perspective, he said.

“I think a lot of the people I talked to like the fact I’ve done both prosecution and defense. ... I’ve seen the issues from both angles,” Deane said. “I’ve practiced throughout the state in a lot of counties.”

Deane acknowledges that he does not have as much trial experience as Stamos. But he said he manages his firm’s criminal defense caseload across the state and has defended clients in cases from drunken driving to rape.

He has handled a number of big cases throughout Virginia, including that of Ashley E. Devolites, daughter of former Virginia senator Jeannemarie Devolites (R), in 2002. The younger Devolites was sentenced to nine years for her role in a five-week string of armed robberies from Virginia to New York.

He also represented Mark Cryer, who was arrested in 2008 for distribution of more than 250 grams of crystal methamphetamine, and was part of a drug ring that operated along the East Coast. Deane was part of the team that defended Jeremy Jaynes, who was charged with felony spamming in 2005. Jaynes conviction was later overturned by the Virginia Supreme Court.

Erik Jurgensen, a partner at Albo & Oblon who was a prosecutor in the Fairfax County commonwealth’s attorney’s office at the same time as Deane, said his colleague has always wanted to be Arlington’s commonwealth’s attorney.

“These opportunities in these offices don’t come around very often. He jumped in with two feet,” said Jurgensen, who added that Deane comes from a family with a great deal of law enforcement background.

Deane’s grandfather was sheriff of Greene County, Va. His father is a former member of the FBI and his uncle is Prince William County Police Chief Charlie T. Deane.

“Even more than that, he is really passionate about Arlington,” Jurgensen said. “He feels really strongly about his community. Combining those two passions has brought him to this point, which I think makes him well suited for this job.”

Stamos, a mother of two teenage sons, is married to Craig Esherick, an assistant professor at George Mason University and former head men’s basketball coach at Georgetown University.

Deane, a father of two girls, is married to Heather Deane, a partner at Bonner, Kiernan, Trebach & Crociata who specializes in litigated claims and business issues.

There is no Republican candidate for the November election.