Innocent until proven guilty. It sounds obvious, but it is a radical demand: the government must prove its case, and you never have to prove you did nothing.
The presumption of innocence means that anyone accused of a crime is treated as innocent until the government proves guilt. The burden of proof rests entirely on the state, and the accused need not prove anything at all.
The standard of that proof is deliberately high: beyond a reasonable doubt. It is far easier to win an ordinary lawsuit than to convict someone of a crime, and that gap is intentional. Society would rather risk letting a guilty person go than convict an innocent one.
The principle is ancient, but the famous modern phrasing came from an English barrister, William Garrow, in the 1790s, who insisted that every person be presumed innocent until proven guilty. The idea echoes the old English jurist Blackstone, who wrote that it is better that ten guilty escape than that one innocent suffer.
It shapes a whole trial. The accused can stay silent, decline to testify, and put the government to its proof, and the jury is instructed that the mere fact of arrest or charge is not evidence of anything.
