Hiring/Renting: Responsibility of a Person Circumcising a Baby
Practical Laws of Islam as per the teachings of Ayatullah Sistani
Ruling 2214
If a person is negligent in circumcising a baby or makes a mistake – for example, he cuts more than the normal amount – and the baby dies or is harmed, then that person is responsible. However, if he is neither negligent nor makes a mistake and the baby dies or is harmed as a result of the act of circumcision itself, then he is not responsible as long as he was not consulted to determine whether the baby would be harmed or not, and he did not know that the baby would be harmed.
-Ayatullah Sistani, Practical Laws of Islam, Hiring/Renting (Ijarah)