TNR groups are quick to say that studies show it to be effective, but they never cite the names of the actual studies and the groups that performed them. It is like the medical recommendation to drink eight glasses of water a day. When researched, the eight glasses a day recommendation is found to be an urban legend. No medical group ever made such a statement. It was a myth repeated over and over until it appeared to be fact. The same goes for TNR's efficiency.
But there are several studies performed by credible groups that show TNR is not successful at all. Among them is a study of two large, long-term TNR programs in California and Florida, published in the Journal of the American Veterinary Medical Association. It showed TNR to be ineffective in reducing cat populations.
Project TNR is a program of the New Jersey Animal Rights Alliance. This organization will say or do just about anything to protect animals. Should what it says be trusted without verification? Are these really the people you want dictating what you must tolerate regarding nuisance animals and how your government must deal with them?
Euthanasia of some animals may be unnecessary in a world designed by the animators at Walt Disney, but we live in the real world.