The Court cannot retroactively modify a child support amount to a date prior to notice of the petition to modify, even where one child to the child support order has emancipated. The fact that a child emancipated (turned 18 and graduated from high school) does not automatically terminate child support for that child where there is another child covered by the child support order. Guerra v. Bejarano, (CA-CIV 05-0407, Decided April 27, 2006).
In Guzman v. Guzman, 175 Ariz. 183, 854 P.2d 1169 (1993), the Court recognized that where there is only one child covered by a child support order, that child’s emancipation (in that case, by marriage) would terminate the child support obligation. Guzman is distinguishable from the Guerra case because the Guerra child support order covered more than one child.
View the case at http://www.cofad1.state.az.us/opinionfiles/CV/CV050407.pdf