これは抜き打ち検査のことです。飲酒運転の検問や相撲部屋の薬物検査などのことです。あまり関係はないような言葉ですが今を逃したら紹介できなくなるのであえてここで触れておきます。snap electionということばが日本語の解散総選挙です。このsnap electionのいみはA snap election is an election called earlier than scheduled. Generally it refers to an election called when no one expects it, usually to capitalize on a unique electoral opportunity or to decide a pressing issue. It differs from a recall election in that it is initiated by politicians (usually the head of government or ruling party) rather than voters. Because the power to call snap elections usually lies with the incumbent, they frequently result in increased majorities for the party already in power, having been called at an advantageous time. Generally speaking, the Prime Minister under such systems does not have the legal power to call an election, but rather must request the election be called by the head of state. In most countries, the head of state always grants such a request by convention, but in some systems (for instance, the semi-presidential system of the Weimar Republic in Germany 1920-1933) the head of state has been known to deny the Prime Minister's request.
http://www.youtube.com/watch?v=DS33eSmdhnY 0:24 an expert explains the reason why this snap election has been called. なぜ突然の解散総選挙なのかについては専門家の解説を聞いてみましょう。