Who exactly shot Dr. Martin Luther King Jr. in the head? And why?

I search this up often, but can never seem to get the accurate answer on the dot. So, I’m asking you guys to see If I can compare It to the online answers.
ONLINE: James Earl Ray
Martin Luther King, Jr. was shot while standing on the balcony of the Lorraine Motel in Memphis, Tennessee. An hour later, he was declared dead. For nearly 50 years, the federal government has maintained that James Earl Ray was the gunman who assassinated King that day.
Link: https://www.history.com/news/who-killed-martin-luther-king-james-earl-ray-mlk-assassination#:~:text=%2C%201968%2C%20Dr.-,Martin%20Luther%20King%2C%20Jr.,who%20assassinated%20King%20that%20day.