Looks like they are actually legal in those states for non disabled hunters with certain restrictions.
New York
Crossbows can be used during the REGULAR firearms seasons in the Northern and Southern Zone, during the LATE muzzleloading and bowhunting seasons, and during the January firearms season in Suffolk County, beginning with the 2011-2012 hunting seasons and continuing until December 31, 2012.
Virginia
Crossbows are legal to use by any hunter. A crossbow license is required during an archery season.
Kentucky
Crossbows may be used in designated weeks, see state regulations. Hunters using crossbows during a firearms deer season must follow all firearm season restrictions, zone guidelines and hunting requirements in effect during firearms seasons. Crossbows are also permitted during muzzle-loader only season. Disabled hunters with a permit may use a crossbow to hunt deer during the bow-only deer season.
Maryland
Crossbows may be used to hunt deer only, with the exception of special crossbow permits for disabled hunters who may pursue all game legal for a vertical bow. All hunters may use crossbows for four weeks of archery season and four weeks of gun season.