Here are two views on communion in the hand—The first from Fr. Sebastian Walshe and the second from Jimmy Akin. Decide for yourself who is right.
Both Fr. Sebastian and Jimmy Akin neglect to mention the fact that communion in the hand started under the Tridentine Mass. The indult was approved in 1969 but the Novus Ordo was not promulgated until 1970. In other words, people were receiving communion in the hand while the Tridentine Mass was in place and this must have been going on for some time before Pope Paul VI decided to allow the practice as an indult so people were not violating the law.