As a licensed veterinary technician of 17 years, I am against allowing unlicensed veterinary assistants placing IV catheters or doing other procedures deemed necessary for a LVT to perform. 

LVTs are required to get a degree, pass a national exam, obtain a license through the VA Board of Veterinary Medicine, and maintain it through yearly continuing education. Continuing education keeps the LVT abreast of new trends in medicine and treatments. A license allows LVTs to perform procedures that aid the veterinarian and the facility we work in a more professional way. LVTs are responsible and held accountable, up to the forfeiture of their licenses, for malpractice. 

Veterinary assistants are not held to the same standards. Many have no formal veterinary training, and therefore no knowledge of anatomy or the effects misplaced catheter might have. They can basically just walk away from a situation with no consequences. The veterinarian then opens themselves up for lawsuits and potential license revocations.