  In this note, we give new examples of type I groups generalizing a previous
result of Ol'shanskii. More precisely, we prove that all closed non-compact
subgroups of Aut(T_d) acting transitively on the vertices and on the boundary
of a d-regular tree and satisfying Tits' independence property are type I
groups. We claim no originality as we use standard ingredients: the polar
decomposition of those groups and the admissibility of all their irreducible
unitary representations.
