Did Cardinal Wuerl violate Church Liturgical Law?

This past Holy Thursday, as with many over the last few years, Cardinal Wuerl washed the feet of twelve men and women. We know this, because of a photo in the Catholic Standard.

According to Church Liturgical Law, only men can be chosen for this (viri selecti). Now, although the USCCB may have received some sort of approval for women to participate, you would think that the would follow liturgical law.