[holden]

US Constitution, Amendment V
No person shall be held to answer for a capital, or otherwise infamous crime, unless on a presentment or indictment of a grand jury

HF

[hanamizu]

Seems pretty clear-cut, but it has never been incorporated to cover the states. A quick google search says that half of the states don’t use them at all. So, they’re required on the Federal level, but not on the state level. It might be similar to the requirement that jury trials are required in civil cases involving more than $20—Amendment VII