U.S. Sen. Lisa Murkowski said Thursday that she did not know that her former fisheries aide had signed a plea agreement for fishing violations months before he resigned.

Arne Fuglvog entered a plea agreement in April with federal prosecutors after admitting he illegally fished 33,000 pounds of sablefish in 2005, netting him an extra $100,000. He faces jail and a fine when he's sentenced next week.

According to Murkowski, Fuglvog told her June 29 that he was entering a plea agreement and faced a hefty fine and jail time. She told him then that she would need his resignation, but let him stay on because he told her the agreement would be filed Aug. 1.

Murkowski says in retrospective, she would have done things differently.