The first Corrie character to die at his own hand was Joe Donelli. He killed Steve Tanner, a murder that Len Fairclough was suspected of committing. Joe had run off but returned a year or so later and held
Janet Barlow was Ken Barlow's second wife. They had a stormy marraige and separated in 1976. In early 1977, she returned and wanted a reconciliation but Ken rejected her. He found her in the morning, dead, having taken sleeping pills.
Don Brennan, who had terminal cancer, tried to get revenge on Mike Baldwin but in the end, drove Alma's little red sports car into the viaduct at the end of the street back in 1997. He died in the resulting fireball. The scorch marks were on those bricks for years until the Joinery was built last year and then all the bricks came down with the tram crash.
Katy Harris killed her father in a fit of rage. Her mother took the blame for it and Katy, a diabetic, overdosed herself on sugar, the guilt she felt having been too much for her.
Those are the only ones I can remember but maybe you can think of anyone else? Some characters, such as Sheila Birtles, Ken Barlow, Les Battersby and Bet Lynch have thought about it but were saved by a friendly face and encouraging word. David Platt drove his car into the canal but was only trying to ruin Sarah's wedding.
Thanks to Corrie.net who list over 120 characters (minor and major) and 2 animals that have died since the start of the Street.