They might use District personnel as support, but they're mainly on patrol answering calls. Many variables when it comes to large scale sporting events/venues etc. But...to answer your original question, I found something on the 7500 series:
The Critical Incident Response Team will be composed of 250 officers and will handle special events, marches, large gatherings and protecting First Amendment rights. Superintendent Brown said the officers would have special training to identify crowd issues and First Amendment training.
Hopefully this answers the question..