Dianne Feinstein has surrendered decision-making on legal matters to her daughter, but the 90-year-old is still one of the most powerful lawmakers in the country

• Dianne Feinstein has reportedly granted her daughter power of attorney over her legal affairs.
• It's unclear the extent to which Feinstein's agreement extends.
• What is clear is the 90-year-old still wields significant power in the Senate.

Democratic Sen. Dianne Feinstein has surrendered at least some of her authority to her daughter, Katherine, a development that once again underlines the precarious nature of the 90-year-old remaining among the most powerful people.