Sue companies [i.e. for racism, fraud, defective products, injury]? These are often class-action lawyers.
Sue people/ companies, for causing death [ie. a factory blowing up, and killing someone, or someone getting serious brain damage in a car accident]? Plaintiff personal injury lawyers.
Sue corporations for stealing ideas? Trademark infringement lawyers.
Defend criminals [not white collar crime, murder and stuff, what is that called?]? Criminal defense lawyers.
There are also estate planning lawyers, intellectual property lawyers, real estate lawyers, divorce lawyers, tax lawyers, med-mal lawyers, corporate lawyers, insurance defense lawyers, entertainment lawyers, bankruptcy lawyers, creditor's rights/collections lawyers, construction lawyers, patent lawyers, franchise lawyers, adoption lawyers, you name it, there's a lawyer that does it. Law is very specialized.
Only if it came about as the result of a lawsuit that went to trial. The parties can ask for the amount to be sealed.