No, there are no statutes that exempt surgeons from assault laws. That is because surgeons, like all doctors, are licensed by the state.
License: a permission granted by competent authority to engage in...an activity otherwise unlawful
In other words, their medical license gives surgeons legal permission to do things the rest of us can’t.
What exactly the license permits surgeons to do, and under what conditions, is heavily regulated. As long they obey those regulations, surgeons are exempt from the assault laws. However, if they violate those regulations, they face a variety of punishments. They may even be charged with assault.
The requirements surgeons must satisfy in order to legally practice medicine include:
- Licenses: All doctors, including surgeons, must be licensed by the state. There are a host of laws, regulations and professional standards that say in detail what this license permits surgeons to do. For example, they do not give surgeons permission to "chop off your arm just for fun."
- Informed Consent: All medical procedures, including surgeries, require informed consent. There are a handful of exceptions, such as in an emergency, but informed consent is the general rule.
- Consent for Incompetents: In cases where someone cannot (is incompetent to) give informed consent, the law specifies who can give consent for them. In general, parents are allowed to give consent for their children.
- Punishments: Medical care providers, including surgeons, who provide bad care that breaks laws, or violates professional standards, face a variety of punishments. These range from going to jail, to paying for damages to losing their license.
Many people argue that surgeons should not be allowed to perform circumcisions. There have even been attempts to make circumcisions illegal.