[quote="CB_Catholic, post:7, topic:326094"]
I do believe it is permissible AFTER the homily for a layperson to make a presentation for a cause. For example, a Sister or a Brother may make an appeal for a mission or for support for retired religious; a layperson may talk about stewardship to kick off the stewardship drive; etc. This is done at our parish occasionally, and high schoolers have spoken. But the homily must be given first. Also, it is probably better to make the presentation after Mass, but I believe after the homily is permitted.
If I am wrong, someone can correct me, but I did read this on CAF when someone asked a similar question.
It used to be allowed, but it is not supposed to be done anymore. Here are the parts of RS that prohibits it.
[64.] The homily, which is given in the course of the celebration of Holy Mass and is a part of the Liturgy itself, "should ordinarily be given by the Priest celebrant himself. He may entrust it to a concelebrating Priest or occasionally, according to circumstances, to a Deacon, but never to a layperson. In particular cases and for a just cause, the homily may even be given by a Bishop or a Priest who is present at the celebration but cannot concelebrate”.
[65.] It should be borne in mind that any previous norm that may have admitted non-ordained faithful to give the homily during the eucharistic celebration is to be considered abrogated by the norm of canon 767 §1. This practice is reprobated, so that it cannot be permitted to attain the force of custom.
[66.] The prohibition of the admission of laypersons to preach within the Mass applies also to seminarians, students of theological disciplines, and those who have assumed the function of those known as “pastoral assistants”; nor is there to be any exception for any other kind of layperson, or group, or community, or association.
The homily is supposed to be about the word of God and not a time for annoucments or appeals. It is appropriate for father to mention it and to allow them to speak right before dismissal, but it should not be given during the homily.