Somebody else's problem

"Somebody else's problem" or "someone else's problem" is an issue which is dismissed by a person on the grounds that they consider somebody else to be responsible for it.

Examples
A 1976 edition of the journal Ekistics used the phrase in the context of bureaucratic inaction on low-income housing, describing "the principle of somebody else's problem" as something that prevented progress. Where responsibility for a complex problem falls across many different departments of government, even those agencies who wish to tackle the issue are unable to do so.

Referring to a team working on a computer programming project, Alan F. Blackwell wrote in 1997 that: "Many sub-goals can be deferred to the degree that they become what is known amongst professional programmers as an 'S.E.P.' – somebody else's problem."

Douglas Adams' SEP field
Douglas Adams' 1982 novel Life, the Universe and Everything (in The Hitchhiker's Guide to the Galaxy comedy science fiction series) introduces the idea of an "SEP field" as a kind of cloaking device. The character Ford Prefect says,

"An SEP is something we can't see, or don't see, or our brain doesn't let us see, because we think that it's somebody else's problem. That’s what SEP means. Somebody Else’s Problem. The brain just edits it out, it's like a blind spot."

The narration then explains:

"The Somebody Else's Problem field... relies on people's natural predisposition not to see anything they don't want to, weren't expecting, or can't explain. If Effrafax had painted the mountain pink and erected a cheap and simple Somebody Else’s Problem field on it, then people would have walked past the mountain, round it, even over it, and simply never have noticed that the thing was there."

Adams' description of an SEP field is quoted in an article of "psychological invisibility", where it is compared to other fictional effects such as the perception filter in Doctor Who, as well as cognitive biases such as inattentional blindness and change blindness.