What type pheasants are you refering to, Ringnecks or ornamental pheasants? Where do you live and what kinds of predators are in your area? Normally pheasants of any type do not free range, definatly not ringnecks. If you raise the chicks by hand as pets and they are of the Golden or Amherst type, maybe, but it would still not be a good idea. All pheasants fly very well, especially Ringnecks. If you have predators in your area the birds will not last long, even if they don't fly away. We raise several types of pheasants on a fairly large ranch and I have had some birds get loose and have stuck around for several weeks as long as they have food and water, but eventually they all disapear if not enclosed in a pen. Pheasants are easy and fun to raise and there are lots of folks on this site that are very knowageable and willing to help you. Good Luck
Free range ringneck pheasants in WI are considered to be property of the state and you need to purchase a small game liscense AND a pheasant stamp to harvest your own birds. Ornamental pheasants are exempt from this if you can prove that they belong to you.
Over all, pheasants are not like free range chickens. They might come back to visit at times but once released, they will tend to be free rather than free range. This speaking, they are prey to all preditors in your area.
I live in tn and have a pen of ringnecks, 1 hen got out, stayed around for 1/2 day, then gone, even though all the rest of the flock was in and guineas were free ranged around the pen to keep her company. poof she is gone. So I would say no. dont let them out, or they are gone.