3-Month AI Trial Lifts Senior Lawyers' Judgment, Splits Junior Skills
Updated
Updated · Google Research · Oct 7
3-Month AI Trial Lifts Senior Lawyers' Judgment, Splits Junior Skills
1 articles · Updated · Google Research · Oct 7
Summary
A 90-day randomized trial of 133 patent lawyers at 11 firms found AI-assisted work improved unassisted redlining scores by 0.32 standard deviations overall, but that gain came entirely from senior lawyers.
Senior lawyers with 7+ years of experience beat controls by 0.45 SD on the no-AI judgment test, while junior lawyers showed no average improvement and instead split into more strong scores and more weak ones.
On drafting tasks where AI was allowed, the tool raised quality by 0.34 SD after 10 days and 0.38 SD after 90 days, with juniors also finishing about 18 minutes faster than controls.
The study suggests AI reliably boosts immediate output but does not automatically build durable expertise; researchers said seniors used it as a 'logic auditor,' while juniors often improved surface work without strengthening core judgment.