LONDON — A two-vehicle collision on an English country road was just an accident, and no charges will be filed against the driver who seemed to have been at fault, prosecutors said on Thursday — the kind of everyday decision that would ordinarily draw no attention.

Except that in this case, the 97-year-old driver in question is married to the queen, has a longstanding reputation for being a bit too fond of going fast and has drivers at the ready to take him wherever he might like to go.

When Prince Philip, the husband of Queen Elizabeth II, had the accident last month, many in Britain and beyond wondered why he was driving at all, and the episode seemed all too familiar to countless people who have tried to persuade their elderly parents to give up the car keys.

It did not help his cause that two people in the other vehicle were injured in the accident, or that the prince, the duke of Edinburgh, was spotted driving again just two days later, this time without wearing a seatbelt, drawing a verbal warning from the local constabulary.