The core promise: no recovery, no fee
A contingency fee means the attorney's fee is contingent — dependent — on actually winning or settling the case. If there's no recovery at all, the client generally owes no attorney fee, regardless of how much work went into the case.
What Rule 4-1.5 actually requires
Rule 4-1.5 of the Missouri Rules of Professional Conduct sets the baseline: a lawyer's fee must be reasonable, measured against factors including the time and labor required, the fee customarily charged locally for similar work, and whether the fee is fixed or contingent. Subsection (c) requires a contingent fee agreement to be in writing, signed by the client.
A stated percentage isn't automatically the final word
In a 2017 Missouri Court of Appeals decision, the court held that a trial judge was wrong to treat a pre-existing contingency agreement as an automatic ceiling on a court-awarded attorney fee in a case where a statute allowed the prevailing party to recover fees. Instead, the agreement is just one factor to weigh alongside the "lodestar" calculation — the hours actually worked, multiplied by a reasonable hourly rate. While that case arose under a fee-shifting statute rather than a standard client-pays contingency arrangement, it illustrates how seriously Missouri courts take the reasonableness inquiry rather than simply accepting whatever percentage was written down.
Expenses need to be addressed in writing too
Beyond the percentage itself, Rule 4-1.5 requires the written agreement to specify whether litigation expenses are deducted from the recovery before or after the attorney's percentage is calculated — a detail that changes the client's net recovery even at an identical stated rate.
No specific percentage written into law
Beyond these procedural and ethical requirements, Missouri sets no specific percentage ceiling for a personal injury or medical malpractice contingency fee. The rate is negotiated privately between attorney and client, commonly ranging from one-third to 40% of the total recovery.