Aggressive Criminal Defense in Northwest Indiana

Need a Shark? Call Mark!

For more than 30 years, Mark K. Gruenhagen has stood between his clients and the full weight of the prosecution — concentrating on felonies at the state and federal level across Lake County and Northwest Indiana.

  • Mon–Fri 9–5
  • Weekend appointments
  • Schererville, IN
Illustration of Mark the Shark: a grinning shark in a pinstripe suit and sunglasses surfs a wave at sunset, briefcase in one fin and a verdict reading “Not Guilty” held high in the other, above the brushed-gold words “Mark the Shark.”
  • 30+ YearsPracticing Law
  • LicensedIndiana & Illinois
  • State & FederalCourts
  • WeekendAppointments

Aggressive Defense Is at the Heart of Every Case

Felonies · State & Federal

An experienced trial lawyer who wins cases in front of juries. Less experienced representation can wrongly convince you a guilty plea is your only option.

When you’re charged with a crime, the prosecution already has a head start. Mark closes that gap. He concentrates on felonies at the state and federal level, and he prepares every case as if it’s headed for a jury — because the best deals, dismissals and verdicts go to the side that’s ready to fight.

We understand the legal process can be extremely trying and difficult. That’s why we focus not just on defending our clients, but on defending them aggressively — fighting for the best possible outcome in their case.

Explore Criminal Defense

  • Trial-Ready From Day One

    Prosecutors know which lawyers will actually take a case to a jury. Mark builds every file with the courtroom in mind.

  • State & Federal Courts

    Licensed in Indiana and Illinois, and admitted in various federal courts and jurisdictions.

  • Straight Talk, No Runaround

    You’ll hear the truth about your case — the strengths, the risks and your real options — in plain English.

  • Available When You Need Him

    Weekday office hours plus weekend appointments, because legal trouble doesn’t keep business hours.

Meet Mark K. Gruenhagen

Experienced Trial Lawyer

Mark K. Gruenhagen

Attorney at Law

  • Indiana University (undergraduate); Valparaiso University School of Law, 1994
  • Licensed in Indiana and Illinois
  • Admitted to the U.S. District Court, Northern District of Indiana, and various other federal courts and jurisdictions
  • Member of the Lake County Bar Association, Indiana State Bar Association and Lake County Criminal Defense Bar

Mark has been practicing defense in Northwest Indiana for more than 30 years. That experience is on your side.

He knows the courthouses, the procedures and the pressure a criminal charge puts on a family. “Mark the Shark” may be the firm’s calling card, but the approach behind it is simple: prepare relentlessly, tell clients the truth, and never back down from a fight worth having.

Our clients are like family. When you call, you get Mark — not a call center.

Wide gold-framed illustration of Mark the Shark in a pinstripe suit and sunglasses, surfing a wave toward a palm-lined sunset shore with a briefcase and a “Not Guilty” verdict, beside the words “Mark the Shark.”

Need a Shark? Call Mark!

Free Case Evaluation

When your freedom, your license or your family is on the line, you want someone in your corner who’s ready to fight. Call now — weekday hours and weekend appointments available.

What Clients Say

In Their Own Words

Mark handled my ticket and got it removed from my record. I’d highly recommend his services.

Larry P.Traffic Ticket

Testimonials do not guarantee a similar outcome. Every case is different.

Serving Lake County & Northwest Indiana

Based in Schererville

From the office on West Lincoln Highway, Mark represents clients in courts throughout the region, including:

  • Schererville
  • Merrillville
  • Crown Point
  • Hammond
  • Gary
  • Munster
  • Highland
  • Dyer
  • St. John
  • Hobart
  • Valparaiso
  • East Chicago

Know Your Rights

Straight Answers

I’ve been pulled over. Should I speak to the officer?

No! Talking to an officer may seem like a good idea, but most often the only outcome is self-incrimination. Stay calm and polite, keep your answers brief, and contact us immediately if you’ve received a ticket or been arrested.

Should I go to court without a lawyer?

No! Walking into court without legal representation puts you at a serious disadvantage against a prosecutor who does this every day. Talk to a lawyer before your first court date.

Should I consent to a search?

No! You can calmly say “I do not consent to a search.” Don’t argue or physically resist — just don’t agree, don’t answer questions, and call your lawyer at (219) 322-3000.

More Questions & Answers

Talk to Mark Today

Free Case Evaluation

If you need legal representation, contact us immediately. Tell us a little about your situation and Mark’s office will get back to you promptly.

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A short summary is perfect — Mark will go over the details with you.

We only use your information to respond to your inquiry.

Reach Mark Directly

Prefer to talk it through? Call the office — weekend appointments are available.

  • Visit
    833 West Lincoln Highway, Suite 450 E
    Schererville, IN 46375
  • Hours Mon–Fri 9:00 AM – 5:00 PM Weekend appointments available

Someone in Custody?Call (219) 322-3000 right away. The earlier Mark is involved, the more options you have.

Call Mark Free Evaluation