[deepsun]

Should be not <found "not guilty">, but <not found "guilty">, I believe.

[nerdponx]

"Not guilty" is a common enough phrase in English that you can use it like an adjective and native speakers will know what you mean. Pedantically, you might want to spell it "not-guilty".

[dragonwriter]

"not guilty" is the usual verdict. One is either "guilty" or "not guilty"; the latter is legally innocent, there is no third state.