Another article has this “It also emerged that one of the fugitives, Rodolfo Godinez, obtained a green card in 2001 and was allowed to stay in the United States despite later robbery and assault arrests, immigration authorities said yesterday.”
If his mother was legal, wouldn’t he have been as well in 2000 before getting this green card?
Yes, but he'd have been a dependent, and thus covered under her legal status. Once he moved out, he'd have had to become legal on his own.