Nicola Sturgeon, Scotland’s Former Leader, Is Arrested in Financial Inquiry

Nicola Sturgeon, Scotland’s former first minister and once one of Britain’s most prominent politicians, was arrested on Sunday by police officers investigating the finances of the Scottish National Party, which dominates the country’s politics and which she led until her unexpected resignation in February.

The news deepens the crisis engulfing the Scottish National Party, or S.N.P., delivering a new blow to its campaign for Scottish independence after the arrests of Ms. Sturgeon’s husband, Peter Murrell, the party’s former chief executive, and then of Colin Beattie, its former treasurer, in April.

Both men were released after questioning and without being charged with any offense. In a statement issued late Sunday afternoon, Police Scotland said that Ms. Sturgeon had also “been released without charge pending further investigation” and, swiftly after that announcement, the former first minister proclaimed her innocence.

“To find myself in the situation I did today when I am certain I have committed no offence is both a shock and deeply distressing,” Ms. Sturgeon wrote on Twitter. “Innocence is not just a presumption I am entitled to in law. I know beyond doubt that I am in fact innocent of any wrongdoing.”

The latest development is a dramatic fall from grace for Ms. Sturgeon, a popular politician who served as Scotland’s first minister for more than eight years until she announced she was stepping down.

Recent events have cast a cloud not only over the S.N.P., whose poll ratings dipped after the party’s funding crisis intensified, but also over its objective of achieving independence for Scotland.

The prospect of an imminent new vote on breaking away from the United Kingdom had already receded before Ms. Sturgeon stood down, but the investigations into the party are a significant setback to the pro-independence forces. Polls show that the Scottish public is broadly split on the issue. A clear and consistent majority for ending the centuries-old union with England has yet to emerge.

In February, the resignation of Ms. Sturgeon took the political world by surprise and prompted a divisive race to succeed her that was ultimately won by Humza Yousaf, previously the health secretary of Scotland.

However, Mr. Yousaf’s efforts to establish himself as the country’s first minister have been overshadowed by the recent escalation of the police investigation into the S.N.P.’s finances.

In line with standard British protocol, Ms. Sturgeon was not named on Sunday in statements from Police Scotland. The initial one said that “a 52-year-old woman” had “been arrested as a suspect in connection with the continuing investigation into the funding and finances of the Scottish National Party,” adding that she was “in custody and is being questioned” by detectives.

Scottish police can arrest someone if they think the person may have committed a crime and if they want to question the person formally. The person can then be released while investigations continue into whether there is enough evidence for charges to be laid.

A statement issued on behalf of the former first minister said: “Nicola Sturgeon has today, Sunday 11th June, by arrangement with Police Scotland, attended an interview where she was to be arrested and questioned in relation to Operation Branchform. Nicola has consistently said she would cooperate with the investigation if asked and continues to do so.”

Operation Branchform, the code name for Police Scotland’s inquiry, began in 2021 and was reported to have followed complaints about the handling of about 600,000 pounds, or about $750,000, in donations raised to campaign for a second vote on Scottish independence. (A first referendum on the question was held in 2014, with Scots voting 55 percent to 45 percent against independence.)

The authorities are thought to be looking into whether money intended to fight for another vote on independence was diverted for a different purpose, and to be investigating why Mr. Murrell made a loan to the party.

Mr. Murrell, who has been married to Ms. Sturgeon since 2010, held the post of chief executive from 1999 until March, when he resigned after accepting blame for misleading statements from the party about the size of its dues-paying membership. Mr. Beattie resigned after his arrest in April.

After Mr. Murrell’s arrest, the British news media reported that the police had seized a luxury motor home parked outside his mother’s house. Mr. Yousaf confirmed to reporters that the party had bought the vehicle — to use as a mobile office for campaigns, officials told local news outlets — but said that he learned about the purchase only after he became leader.

In a BBC interview broadcast on Sunday before news of the arrest, Mr. Yousaf refused to comment on the police investigation. But pressed on the impact of the crisis, he said that supporters “should be absolutely confident that, despite having some of the most difficult weeks our party has probably faced, certainly in the modern era, that support for independence is still rock solid.”

Asked if Ms. Sturgeon was OK, Mr. Yousaf replied that “she’s in a good place and doing well for sure,” adding that he had spoken with her to take advice from “arguably one of the best politicians” that Europe had seen in recent decades.

When Mr. Yousaf won the leadership of the party, he was seen as the continuity candidate who would retain most of the policies of his predecessor. At that time, and given Ms. Sturgeon’s stature, that was an advantage in the race that he narrowly won.

But when the financing crisis escalated, all of that changed. Mr. Yousaf has struggled to emulate his predecessor’s dominant political profile. The S.N.P.’s problems have encouraged the opposition Labour Party, which hopes to make gains in Scotland in the next general election that is expected in the second half of 2024.

Ms. Sturgeon became party leader and first minister in 2014 after the resignation of her mentor Alex Salmond, with whom she would later fall out in spectacular fashion.

A member of the S.N.P. from the age of 16, Ms. Sturgeon became known as one of Britain’s most effective communicators and was seen as a sure-footed leader during the coronavirus pandemic. While leading the Scottish government, which has its own distinct powers, she outlasted four British prime ministers as she pushed for independence.

Achieving that goal ultimately proved beyond her. For a referendum to be legally binding, it needs the approval of the government in London. Successive British prime ministers have refused to countenance another vote, arguing that the one held in 2014 settled the issue for a generation. The Labour Party says it would not change that policy if it were to win the next general election.

At the time of her resignation, Ms. Sturgeon explained her decision by saying she was exhausted and had become too polarizing a figure in Scottish politics to persuade wavering voters to support independence.

When asked by the BBC in April if the police investigation of Mr. Murrell had prompted Ms. Sturgeon’s resignation, Mr. Yousaf replied, “No, I believe Nicola Sturgeon absolutely that she had taken the party as further forward as she possibly could.”