Nicola Sturgeon has said she was "not even considered for prosecution" during the police probe into SNP finances.
The former First Minister also insisted it was an "important point of principle" that she will not apologise for the crimes of her estranged husband, Peter Murrell.
The ex-SNP leader was appearing at the Edinburgh International Book Festival alongside former Finnish prime minister Sanna Marin.
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Murrell, the former chief executive of the SNP, was jailed for five years and three months earlier this year after pleading guilty to embezzling more than £400,000 from the party.
Ms Sturgeon was arrested and questioned for several hours in June 2023 as part of the investigation into the SNP's funding and finances. She provided no-comment answers during her interview under caution at Falkirk police station.
She then provided both Police Scotland and the Crown Office and Procurator Fiscal Service (COPFS) with what she said was a "very detailed written document answering the questions that had been put to me".
A standard prosecution report was submitted to the Crown against Murrell on May 23, 2024. It outlined a single charge of embezzlement covering hundreds of purchases.
A separate report covering Ms Sturgeon and Mr Beattie made no recommendation for charges, instead seeking "advice and guidance" on whether there was sufficient evidence to continue inquiries.
Police Scotland had considered there was enough basis for arrests and questioning. However, the Crown ultimately determined there was insufficient admissible evidence of criminality to justify further action.
Addressing the audience on Tuesday, Ms Sturgeon said: "I have been utterly cleared after a very stressful two-year investigation, totally cleared, was not even considered for prosecution."
When asked whether she owed party members an apology in the wake of Murrell's crimes, the former SNP leader said: "I am very, very, very sorry that it happened," adding that she was "more sorry than I can ever find words really to properly convey."
"I have been a member of the SNP since I was 16 years old, the SNP is my extended family, I love it, and I don't say that lightly," Ms Sturgeon said.
