To get away with murder.
Selbst mit Mord davonkommen.
The idea here is that murder (obviously) is a serious crime. You're almost literally getting away if you're never charged. Same in English and German.
Forge the boss's signature? You won't get away with that.
Die Unterschrift vom Chef fälschen? Damit kommst du nicht durch.
The point here is that this is not "going to fly". Which in German is rendered as it "won't get through". It has a less serious connotation. Somewhat less. It's still a serious offense after all.
Take a day off without telling anyone? I can get away with that.
Einen Tag frei nehmen, ohne jemandem was zu sagen? Das kann ich mir erlauben.
This is the least serious of the offenses. Basically, not that big a deal. Here you convey the notion that you may as well take the liberty of doing that, as nobody is going to stop you.
So the best translation in a given situation is a matter of degree. The last one is often used as it works in a variety of contexts. While the suggestions in the other answers are not wrong, you may as well work "es sich erlauben können" into these sentences:
Singers can get away with less talent today because they have computers to help them.
Sänger können sich heutzutage weniger Talent erlauben, da ihnen ja Computer helfen.
And:
In this industry, you can't get away with working less than 40 hours a week.
In diesem Geschäft kann man es sich nicht erlauben, weniger als 40 Stunden die Woche zu arbeiten.
