About Clarissa

What Clarissa does

Clarissa is AI evidence review for criminal defense. A DUI or other criminal case arrives as a police report and hours of video from body cameras, dash cameras and station cameras, and the defense has to find where the footage and the report disagree. Watching every minute and reading every page takes days a firm does not have, so discrepancies go unfound.

Clarissa watches every second of every camera, transcribes what was said, reads the report, and checks each claim the report makes against what is on screen. Every finding is pinned to the exact moment on camera, and a panel of built-in experts asks the questions a defense specialist would: field sobriety testing, constitutional issues, chemical testing, the report itself and more. The attorney reviews the findings, jumps to the footage, asks follow-up questions, and exports the report as PDF, Word or plain text.

It is built for defense attorneys and the firms they work in, above all DUI defense, where the video is the case.

The product today

Clarissa is live at getclarissa.ai. A firm signs up on this site, creates a case, uploads the report and the videos, and reviews the findings in the workspace shown on the front page. Sign-up is open to any defense firm.

The product launched in 2026 and is in use by defense attorneys on their cases today.

The people behind Clarissa

The founders of Clarissa AI, Inc. bring decades of enterprise technology and go-to-market experience to evidence review for defense attorneys.

Randy Johnstone

Co-founder & CEO

With more than 15 years of experience in enterprise sales, SaaS, fintech, and go-to-market strategy, Randy has built his career helping technology companies bring innovative solutions to market and drive meaningful customer adoption.

His experience spans early-stage technology companies and large enterprise organizations, where he has led complex sales initiatives, developed strategic partnerships, and worked closely with executive leadership teams. At Clarissa AI, Randy leads the company's business strategy, growth, and mission to help DUI defense attorneys review evidence more efficiently, thoroughly, and confidently.

William S Johnstone

Co-founder & CTO

William Johnstone is a highly accomplished technology architect with over two decades of professional software development experience building high-availability cloud infrastructure and scaling complex global platforms. As Co-Founder and CTO of Clarissa.ai, he leverages advanced artificial intelligence and automation to transform video evidence evaluation, streamlining critical, high-stakes workflows for defense attorneys.

Over his career, William has built systems for health tech, fintech, retail and telecommunications: digital therapeutics platforms that met strict international compliance rules, large telecom modernizations, and secure core financial processing. He leads by serving and mentoring his teams, and cares about engineering cultures that put people first.

Clarissa AI on LinkedIn hello@getclarissa.ai