The Promise and Reality of Speech-to-Text Technology

In recent years, speech-to-text (STT) technology has seen a surge in demand across various industries, and the legal system is no exception. Just as video conferencing became a necessity for courtrooms during the COVID-19 pandemic and is now commonplace, automated transcription solutions are now being sought to improve efficiency, accessibility, and record-keeping in legal proceedings.

However, while STT is an exciting advancement, it is not without limitations. Many courts assume that simply implementing STT will produce near-perfect transcripts, but the reality is more complex. For courts looking to adopt automated transcription solutions, understanding the factors that influence STT accuracy is crucial. The most significant determinant? Audio fidelity.

The Critical Role of Audio Quality in Speech-to-Text Performance

The single most important factor affecting STT results is the quality of the audio being captured. Stuart Herring, Managing Director at Redfish Technologies, who has implemented STT solutions at over two dozen sites, emphasizes that audio fidelity outweighs all other variables in determining accuracy. 

When high-quality audio is captured—free of background noise, transient sounds, and echo—some STT systems can achieve Word Error Rates (WER)¹ as low as 5%. However, as soon as audio quality declines, transcription accuracy deteriorates just as quickly.

A study by the National Library of Medicine² demonstrates this effect. Under optimal conditions, Google Cloud Speech API achieves a WER of 6.6%. When exposed to less-than-ideal conditions, that WER more than doubles to 13.6%, highlighting the stark impact of compromised audio quality.

Why Equipment Alone Isn’t Enough

Given the importance of high-fidelity recordings, upgrading microphones and digital signal processors (DSPs) seems like an obvious solution. And indeed, premium recording equipment—such as Q-SYS Core 110f or Biamp Tesira Forte DSPs, paired with Dante IP protocol—can significantly enhance captured audio quality while simplifying connectivity.

However, courtroom environments pose unique challenges. Better equipment does not change human behavior. Participants frequently turn their heads, speak softly, or mumble. Unlike controlled studio environments, courts deal with unpredictable speech patterns that even the best microphones cannot fully mitigate.

Brad Uthe, Director of Business Development at BIS Digital, underscores this reality: “Garbage in gives you garbage out.” No matter how advanced an STT system is, poor audio input leads to poor transcription results. Courts must account for both equipment and real-world courtroom dynamics when scoping solutions.

The Overlooked Factor: STT Configuration and Setup

Beyond audio fidelity, another commonly overlooked factor is STT system configuration. Even with ideal audio conditions, transcription accuracy can be affected by:

• Internet connectivity: Cloud-based STT engines require stable, high-speed internet connections.

• The STT engine used: Not all engines handle legal terminology and multi-speaker environments equally well.

• Customization and training: Some engines improve with domain-specific tuning, but generic setups may struggle with legal jargon and complex dialogue.

Bridging the Gap Between Speech-to-Text and Courtroom Accuracy

With all these variables at play, courts must take a holistic approach to STT adoption. High Criteria Inc. developed Liberty Notes Plus not as just another STT tool, but as a solution designed to enhance courtroom transcription workflows while addressing STT’s inherent limitations.

Unlike traditional STT solutions, Liberty Notes Plus allows real-time human annotation without altering the original transcript. Court staff can insert highlighted bookmarks for later review, preserving the integrity of both the raw STT output and the courtroom audio recording.

Furthermore, the system generates synchronized Word documents linked to Liberty Player, allowing transcripts to be played back with the original recording—offering courts a verifiable, reviewable transcript rather than blindly trusting AI-generated results.

The Bottom Line

For courts considering STT solutions, the takeaway is clear: accuracy depends on more than just AI. Audio fidelity, courtroom conditions, and STT system setup all play critical roles in transcription quality. By recognizing these factors and integrating a hybrid approach like Liberty Notes Plus, courts can maximize STT effectiveness while ensuring reliable, trustworthy records.

For more information, contact [email protected].

Additional Resources:

• Brad Uthe (BIS Digital): 
  [email protected]

• Stuart Herring (Redfish Technologies):
  [email protected]

1  Word Error Rate (WER) measures the percentage of words that are incorrectly transcribed by the speech-to-text system relative to the total number of words transcribed. Although a WER evaluation has its limits, it remains the most widely used and accepted method for evaluating speech-to-text results.

2  Ferraro et al, “Benchmarking open source and paid services for Speech to Text” National Library of Medicine, September 20, 2023, https://pmc.ncbi.nlm.nih.gov/articles/PMC10548127/#B10, Retrieved January 3, 2025