May 23 is the 143rd day of the year (144th in leap years). There are 222 days remaining.
- 1892 — Frederick Deeming died.
- 1936 — Adolf Seefeldt died.
- 1950 — Richard Chase is born.
- 1951 — Catherine Birnie is born.
- 1964 — Cheryl Wims (victim) is born.
- 1978 — John Wayne Gacy's suspected victim, Charles Hattula, is found.
- 1979 — James Miller is apprehended.
- 1980 — David Van Dyke is apprehended.
- 1981 — Linda Sutton is murdered by the "Ripper Crew".
- 1982 — Carl Watts is apprehended.
- 1983 — Cheryl Lee Wims is murdered by Gary Ridgway.
- 1988 — Elaine Shereika is murdered by Alexander Wayne Watson.
- 2001 — Chang Lin is murdered by Gao Chengyong.
- 2018 — Agustín Ramón Martínez is apprehended.
- 2019 — Bobby Joe Long died.
- 2023 — Shavkat Shayakhmedov died.