Wiktionary
suicide by cop
n. (context informal English) The method of suicide where a person deliberately acts in a threatening way towards a police officer, with the purpose of being shot as response.
Wikipedia
Suicide by cop
Suicide by cop is a suicide method in which a suicidal individual deliberately behaves in a threatening manner, with intent to provoke a lethal response from a law enforcement officer.
Usage examples of "suicide by cop".
You hear about people committing suicide by cop, but I figured this guy was planning suicide by robber.