Drug trafficker Gejmund Capelen was sentenced to 15 years's imprisonment for drug smuggling and corruption, reports broadcaster NRK.
The court gave Jensen the longest possible sentence, saying that there were no mitigating circumstances, according to the report.
Additionally, Jensen was employed in several leading police roles during the period in which he committed the crimes, according to the judgement issued by the court.
“Jensen's actions are seriously damaging to the public confidence on which the police and rule of law depends,” Oslo District Court presiding judge Kim Heger said according to NRK.
Heger added that that case was without precedent in Norwegian legal history.
Norway regularly tops international rankings as one of the world's least corrupt countries.
“Corruption undermines confidence in the legal apparatus and important principles on which society is built,” Heger said.
667,800 kroner (89,700 euros) as well as weapons gained through corrupt activities will also be confiscated from Jensen, according to the report.
Both Jensen and Cappelen will consider appealing the court decision. Appeals must be made within 14 days of sentencing.
Cappelen, whose sentence was reduced by 30 percent, was given 15 years in prison, also for corruption and smuggling of marijuana.
The drug smuggler's sentenced was reduced due to his cooperation in providing information that led to the conviction of Jensen.
“Cappelen's testimony was crucial in resolving this very serious case. Nevertheless, the court finds Cappelen to have acted cynically and systematically and his drug smuggling operation is without equal in Norway's history,” said judge Sven Olav Solberg according to NRK.
A former head of fighting organised crime, Jensen was initially arrested in 2014 on suspicion of corruption and being connected to Cappelen's drug ring, months after Cappelen himself was taken in by police on December 19th 2013 on suspicion of drugs-related offences.
Jensen allegedly received 2.44 million kroner (over 262,000 euros) in bribes, in exchange for helping Cappelen smuggle 13,9 tonnes of hashish into Norway between 2004 and 2013, prosecutor Guro Glærum Kleppe said in May this year.
Oslo District Court on Monday found Cappelen guilty of importing 16.8 tonnes of the drug between 1993 and 2013.
Jensen failed to convince the court that a series of SMS messages presented in evidence were not related to drug smuggling, according to NRK's report.
“The court finds that the SMS messages clearly relate to the import of hashish. The network communicates in simple codes, Jensen gives Cappelen reassuring messages. The court finds it clear that messages about sunshine communicate that Cappelen is not in the sights of police and can safely import his cargo,” Heger said in court.
The judges added that they did not believe Jensen's claims that he was not aware that Cappelen was importing hashish.
“It has been shown beyond reasonable doubt that Jensen, during the period in question, was well aware of Cappelen's import,” Heger read to the court.