They were unhappy with "disincentives" to owning an electric car, including road tolls. So they drove repeatedly through toll stations without paying. Every time, they received a fine, which they didn't pay. According to the rules, the car was then confiscated.

Photo: Bellona.

When confiscated, the car was auctioned, but since no-one else wanted to buy the car, only our heroes were at the auction to buy it back again. They they drove without paying tolls, car confiscated again, car auctioned again, bought back again... and this went on, and on, and on.

The fine was 300 Norwegian crowns each time, and they bought the car back each time for 200 Norwegian crowns (i.e., for less than the fine).

Source: https://www.aftenbladet.no/aenergi/i/gRKq5/frederics-droemmebil

Finally, in 1996, the team had their way and electric cars were exempted from paying road tolls, the star power of A-ha helping along the way. Presumably the government just gave up, since exempting one car wasn't going to break the bank.

Source: https://bil24.no/norges-elbil-pioner-hedret/

These early efforts were important in the long process (starting with the oil crises in the 1970s) of developing interest in electric cars in Norway, from a few individuals through to 2020's extraordinary record 54% of all new cars sold being battery-electric.

For more on the historical of electric cars in Norway from the 1970s, check out TØI's report here (in Norwegian).
https://www.toi.no/getfile.php?mmfileid=33261#page=37

Note that while some sources say that the converted Fiat Panda was in 1989 the first electric car in Norway, the history goes a bit further back. https://www.tu.no/artikler/norges-eldste-elbil-ga-rekkeviddeangst-allerede-i-1902-fremdeles-skremmer-den-vettet-av-eieren/445731