Thomas Gjostein

Attorney and Partner

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Professional Experience

Thomas Gjostein’s parents first noticed his ability to argue his case at the dinner table at a young age, and it was later when reading the famous novel To Kill a Mockingbird that he first developed an affinity for defending the oppressed and the less fortunate.

“My mom and dad told me they thought I’d make a good lawyer because I was good with this muscle,” says Gjostein, pointing to his mouth. “They realized at a young age that I was good at talking. And then I read To Kill a Mockingbird and it had a big impact on me. Here was a lawyer in a small southern town standing up for someone being accused (of rape) because he was the wrong color.”

After observing prejudice first-hand growing up in the 1970s, Tom had developed an interest in becoming either a lawyer or writer by high school and went on to study at the University of Michigan. By then, a lawyer, who doubled as a best friend’s father, asked him the same question he now asks law students today.

“Do you want to stand up for people who can’t stand up for themselves, for causes that aren’t popular?” says Gjostein. “If you don’t want to do that, you’re probably in the wrong field. That’s what it’s all about. You have to believe in what you’re standing up for, you have to want to stand up for the little guy. For those who cannot speak for themselves.”

That “helping out the little guy” theme is at the heart of the Siewert & Gjostein law firm. Practicing with partner Michael Siewert in Columbus since 2010, Gjostein says their philosophy includes “never to quit on our clients” and to “not leave any stone left unturned” when working a case. Siewert and Gjostein have a combined 65 years of courtroom experience.

“We’ll go over the OVI video with our clients, where plenty of attorneys won’t do that,” he says. “The State of Ohio has to go through us to get to my guy. If they have a trumped-up case, they have to go through us.”

In more than three decades of winning not guilty verdicts and getting cases dismissed, Gjostein has walked countless clients out of the courtroom freely. He has a documented reputation for successful case resolution through years of working drunk driving, DUI and OVI defense — as well as serious felony and misdemeanor criminal cases. Tom has won major jury trials with not guilty verdicts for aggravated murder, murder, aggravated robbery, and other felonies and misdemeanors.

A 1988 graduate of the Capital University School of Law, Gjostein has devoted a large portion of his career to the defense of the indigent, working as a Franklin County Public Defender for a number of years. During that time, he tried many jury trials with successful results and maintained one of the highest rates of dismissal and resolution of cases to lesser charges. With the Public Defender, Tom represented thousands of clients a year and a large percentage of those cases involved drunk driving defense. He also trained new attorneys in trial casework and evidence assessment.

He then joined the Common Pleas Unit and represented clients charged with serious felonies. He has attended the National College for DUI Defense, an intensive seminar in Drunk Driving Defense, and is also certified as a Guardian ad Litem with the Franklin County Domestic and Juvenile Court.

As a team, he says, Siewert & Gjostein works a high rate of cases that either get dismissed, sent to trial or acquitted — or a "case resolution with the least amount of risk” for clients.

“That’s what we do,” he says.

Practice Areas

  • DUI/OVI Defense
  • Murder
  • Robbery
  • Domestic Violence
  • Major Traffic Violations
  • Minor Traffic Offenses
  • Theft, Forgery, Receiving Stolen Property
  • Sex Offenses
  • Juvenile Defense
  • Guardian ad Litem
  • Parental Representation in Abuse, Neglect and Dependency cases
  • Bankruptcy


  • Law School
    Capital University Law School, J.D., 1988
  • Undergraduate
    University of Michigan, B.A., 1985

Bar Admissions

  • Ohio, 1988
  • United States District Court, Southern District of Ohio, 1989


  • American Bar Association
  • Ohio State Bar Association
  • Columbus Bar Association
  • National Association of Criminal Defense Lawyers
  • Ohio Association of Criminal Defense Lawyers
  • Central Ohio Association of Criminal Defense Lawyers
  • Central Ohio Association of Juvenile Lawyers


  • National College for DUI Defense, an intensive seminar in Drunk Driving Defense
  • Certified as Guardian ad Litem with the Franklin County Domestic and Juvenile Court

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