Sturgeon was Scotland's longest-serving first minister, in charge of the devolved Edinburgh administration, leading her Scottish National Party (SNP) to a series of resounding electoral successes before her abrupt resignation a year ago.
Her legacy has been damaged by a police investigation into the SNP's finances during her leadership, the SNP's falling popularity and increasing questions over her transparency in handling the COVID-19 pandemic.
On Wednesday she testified at the COVID inquiry, having been criticised for her using - and deleting - WhatsApps while she was co-ordinating the response of the Scottish government to the COVID crisis.
Asked if she had deleted the WhatsApps, she said "yes".
Sturgeon said her use of WhatsApp was "extremely limited and... would not relate to matters of substantive government decision-making," and that she retained pertinent information even when messages had been deleted.
But she accepted she told a journalist that her WhatsApps would be released when she knew they had been deleted, and apologised if her answer to him had been unclear.
"I am certain that the inquiry has at its disposal anything and everything germane to my decision-making during the process and the time period of the pandemic," she said.
"I was very thorough... to ensure that things were appropriately recorded, but in line with the advice I'd always been given, since my first day in government, probably, was not to retain conversations like that on a phone that could be lost or stolen."
The COVID inquiry is examining the responses of government officials to the pandemic and whether mistakes were made. It was formally set up in June 2022 and is expected to last for years.
(Reporting by Alistair Smout; Editing by Andrew MacAskill and Christina Fincher)
By Alistair Smout
