You can get sued for anything, and you can lose if you get an incompetent or crooked lawyer, judge, jury, witness, cop, etc.
Slander and libel laws might protect you somewhat from slander and libel laws, but there are a million other ways a crooked lawyer get get you — “settling out of court”, as this lawyer mentioned, is the holy grail for scumbag lawyers (the norm).
The only way to win with honor in the court system is to play beyond their rules, and not get caught.
The best way to win in court is to be so broke (on paper, at least) that you're judgment-proof. :-)