Fault rules answer two different questions
A fault system can affect whether a claimant may recover at all and how an allowed recovery is reduced. It does not by itself decide who was negligent, what caused the injury, or the amount of legally recoverable damages.
Pure comparative systems reduce proportionately
In a pure comparative system, claimant fault generally reduces recoverable damages by the assigned percentage without a fixed 50% or 51% cutoff. California, Washington, and Arizona use proportional approaches for ordinary negligence, subject to each state’s scope and exceptions.
Modified systems add a cutoff
A modified system reduces damages up to a statutory threshold and bars recovery beyond it. Wording matters: Texas and Illinois use a greater-than-50% formulation for covered claims, as does current Florida law for many negligence actions.
Contributory negligence can be an all-or-nothing defense
A small number of jurisdictions retain a rule under which claimant negligence can bar recovery, subject to local doctrines and exceptions. Do not import a neighboring state’s rule into the analysis.
Evidence comes before percentages
Preserve scene records, witness information, reports, photographs, product information, and communications. A percentage is a factual and legal conclusion, not something a directory or calculator can assign from a short description.