On Jan. 6, as the state's lead-paint trial entered its third month, lawyers for some of the nation's biggest paint companies gathered in the conference room of a Providence law firm to depose their nemesis, Attorney General Patrick C. Lynch. For nearly 4 1/2 hours, the lawyers grilled Lynch about his decision to drop DuPont from the case, in return for DuPont's promise to donate $12.5 million to address childhood lead poisoning in Rhode Island. The paint companies were challenging the agreement, announced in June 2005, because if they were found liable in the ongoing trial, they faced the possibility of having to pay more to clean up the damage with DuPont out of the case. Tensions ran high, reflecting the high stakes and historic nature of a seven-year legal struggle that has captured national attention.