EWTN Catholic Q&A
Funeral Mass
Question from Father Joe Vatter on 04-19-2005:

Are not the color of the vestments for the funeral liturgy usually white? Why were the Celebrant and con-celebrants vested in red?

Answer by Colin B. Donovan, STL on 04-26-2005:

Since Peter is a martyr, the Popes have taken crimson as their personal liturgical color.