Three Strikes，在法律语境中指的是“事不过三”。

Three Strikes：legislation providing that an offender's third felony is punishable by life imprisonment or another severe sentence.

Three Strikes源于美国的棒球运动。棒球用语有一句名言"Three strikes，and you are out"，意思是在棒球比赛中，击球手若三次都未击中投球手所投的球，则必须出局。引申至法律，

Three Strikes Law，也称三振出局法，规定，因暴力或严重罪行"进宫"两次者，以后每再犯一次，无论新罪严重与否，都要受到重判甚至是终身监禁。该法旨在严惩累犯。

参考双语例句：

The three strikes law has reduced the state’s crime rate and prevented criminals from being recycled through our courts over and over again.

三振法已經降低了加州的犯罪率，防止我們的法院一而再、再而三地回收處理罪犯。

In 1994, California adopted, through both its legislature and a popular referendum, what it called a "three strikes law", designed to reduce violent crime.

早在1994年，通过州议会与全民公决，加州开始实行被称之为“三击出局法”的法律，该法律的制定意在减少暴力犯罪。

To that end Vivendi has lobbied successfully for a so-called “three strikes” law in France, under which those who download pirated music can lose internet access.

为了终止非法在线下载音乐，威望迪已成功游说法国通过“三振出局”法①，这将让那些下载非法复制音乐的人无法访问互联网。

However, we find that relatively weak passwords, about 20 bits or so, are sufficient to make brute-force attacks on a single account unrealistic so long as a “three strikes” type rule is in place.

然而，我们发现，长度约为20个字符左右、相对较“弱”的密码也已经能够使得针对单一账户的暴力破解变得不现实：只要有“三振出局”的规范即可。 （译者注：原文的“three strikes” type rule 指的应该是连续三次输入错误密码就会暂时锁死账户，具体可参考此处。）