Former Malaysian Prime Minister Najib Razak has been found guilty and sentenced to 15 years in prison in his second major trial involving the multibillion-dollar 1MDB scandal.

The ruling was handed down by the Kuala Lumpur High Court on Friday, where Najib, 72, was found guilty on all 21 counts of money laundering and four counts of abuse of power in the illegal transfer of 2.2 billion Malaysian ringgit ($543m) from Malaysia’s 1MDB sovereign wealth fund into his accounts.

“The contention by the accused that the charges against him were a witch hunt and politically motivated were debunked by the cold, hard and incontrovertible evidence against him that pointed towards the accused having abused ‍his own powerful position in ⁠1MDB, coupled with the extensive powers conferred upon him,” Judge Collin Lawrence Sequerah said in his verdict.

Prosecutors accused Najib of abusing his position as prime minister, finance minister and 1MDB advisory board chairman by moving large amounts of money from the sovereign wealth fund to his personal accounts more than a decade ago.

The former Malaysian leader was sentenced to 15 years in jail for each of his four counts of abuse of power and five years for each of the 21 charges of money laundering, all to be served concurrently.

Najib was found guilty in 2020 and sentenced to 12 years in prison for misappropriating about $9.9m in 1MDB funds.

His sentence was later commuted to six years.

This latest trial, Najib’s second, was widely considered the most significant to date because it directly involved 1MDB entities and much larger sums of money.

The marathon legal proceedings have spanned seven years and saw lawyers call 76 witnesses to the stand, including Najib himself.

“The trial has had a lot of delays, and it’s a very complicated thing to understand,” said Bridget Welsh, an honorary research associate with the University of Nottingham Asia Research Institute Malaysia.

“These financial crimes are multi-layered, and it’s been a long, extensive process,” Welsh told Al Jazeera.

Najib apologised last year for mishandling the 1MDB scandal, but during his recent trial maintained that he had been led astray by the fugitive Malaysian financier Jho Low, who has been wanted by Interpol since 2016.

Judge Sequerah said on Friday that evidence indicated Najib had an “unmistakable bond and connection” with Low, who served as the prime minister’s “proxy and intermediary”, the Reuters news agency reported.

The judge also challenged Najib’s defence that he mistakenly believed some of his ill-gotten funds were “donations” from the Saudi royal family, Reuters said.

“The accused was no country bumpkin,” said Sequerah, whose reading of the ruling took five hours.

“Any attempt to paint the accused as an ignoramus who was hopelessly unaware of the misdeeds going around him must therefore, fail miserably.”

‘A test of Malaysia’s judiciary’

The 1MDB scandal was a watershed moment for Malaysia when it broke in 2015 and helped unseat the United Malays National Organisation (UMNO) in 2018 after six decades in power.

Despite the scope of the charges against him, Najib is still popular among some Malaysians and his trial remains a “red line” issue for the UMNO, according to Kuala Lumpur-based political analyst James Chai.

Chai told Al Jazeera that Friday’s verdict could also threaten the future stability of Prime Minister Anwar Ibrahim’s unity government.

The UMNO is a member of the coalition, but there have been calls for the party to withdraw. Chai said the trend may accelerate following the ruling.

“While the judgement was fair and appropriate, without obvious lapses, the conviction on all charges could be interpreted as ‘harsh’ by Najib supporters at a time of shifting political sentiments in Malaysia,” Chai said.

“The irony is that the anticorruption credentials that propelled this government to its ascendancy may now serve as a burden,” he continued.

With sentencing and an appeals process still to come, the Asia Research Institute’s Welsh told Al Jazeera that the outcome of Najib’s trial will demonstrate the strength of political accountability in Malaysia.

“This is a test of Malaysia’s judiciary, and it’s a test of political will to allow this to continue, especially given that the party involved is also part of the government,” she said.