Short answers, pulled from the story.
The Foreign Intelligence Service of Ukraine claims Russia has recruited between 140,000 and 180,000 convicts to fight in Ukraine. This figure represents the total number of prisoners mobilized by Russian authorities during the conflict.
According to The New York Times, Wagner's prison recruitment campaign started in early July 2022. Yevgeny Prigozhin personally appeared in prisons around St. Petersburg to offer deals to inmates at that time.
Vladimir Putin signed a law on the recruitment of convicts to contract service with the Defense Ministry on the 24th of June 2023. This legislation disbanded Storm-Z units and replaced them with new Storm-V units under state control.
Under the Wagner model, prisoners who survive a six-month term on the front are released into Russian society. They receive a pardon for their crimes upon completion of their service obligation.
The Institute for the Study of War observed in February 2025 that Russia had mostly exhausted its prison population in 2022 and 2023. The government could no longer generate significant forces from inmates at that time due to depletion of available recruits.