The phrase "case basis" means that each situation or example is evaluated individually, and decisions are made based on its specific circumstances and details. Full definition
To mitigate the level of risk in civil cases, there are databases to consult that accumulate data on jury awards in cases based on certain criteria. (lawyerist.com)
Remember that riders come with a base policy — in case the base policy is discontinued, the rider will lapse too. (pnbmetlife.com)
This is decided on a case by case basis with only very general rules that apply. (law.stackexchange.com)