The alleged Capitol rioter accused of swiping Nancy Pelosi's laptop -- possibly intending to give it to Russia -- has turned herself in, but she's not facing theft charges ... yet.
Instead, the feds have booked Riley Williams for the same slew of charges as several other alleged insurrectionists -- basically, trespassing, violent entry and disorderly conduct. She was seen on video taking part in the Capitol attacks, and according to court docs ... appeared by a staircase near Pelosi's office.
In the docs, the feds say Williams' former partner contacted the FBI several times in the days after Jan. 6, claiming Williams planned to give Pelosi's laptop or hard drive to a friend ... who would turn it over to Russian intelligence.
The partner claimed she'd seen video of Williams swiping the laptop from Pelosi's office -- but the Russia plan fell through. The partner claims Williams still has the laptop or she destroyed it.
The FBI says the theft allegation's still under investigation.
As you know ... Pelosi's office was a hot spot for the insurrectionists, who included Richard Barnett, the man who was photographed with his foot up on her desk.
Barnett -- who left a "nasty note" behind for Pelosi and took a piece of her mail -- was arrested on multiple criminal charges.
No word yet on when Williams will appear in court.