The country singer-songwriter was presented the award at a star-studded prizegiving in Wellington last night for her bluesy soul number Walk.
The Silver Scroll is the annual award for the New Zealand song of the year, as voted for by 10,000 New Zealand songwriters who are members of the Australasian Performing Rights Association.
Neilson grew up singing and performing with her family - including her brother Joshua, who co-wrote Walk - in her native Canada, but has made New Zealand her home for the last nine years, and is married to a Kiwi.
She's already won three New Zealand Music Awards for Best Country Album in 2009, 2010, and 2012, and has contributed greatly to the local music community with her huge soulful voice and entertaining on-stage presence.
The Silver Scroll is a particularly special accolade for Neilson because it's a wide-open contest, and not genre specific - her competition included songs by the Phoenix Foundation, Broods, Tiny Ruins, and Louis Baker.
"This is really special to me. I feel like I'm going to wake up tomorrow and think I dreamt about winning the Silver Scroll,'' she said.
''While the Tuis are of course something I'm extremely proud of, and were a huge achievement, they were limited to a genre. The Silver Scroll transcends genre, and it's about your merits in the eyes of your peers as a songwriter. It's wonderful that with this award, people aren't saying 'It's a great country song', they're just saying 'It's a great song', which is really special."
As for the song, Neilson's Walk manages to distill one of humanity's most-lamented tribulations - the temptation to be with someone you just know won't do you any good - into a swinging, heartfelt, three-minute song.
Its relative technical simplicity is a brilliant framework for great sassy, southern attitude, plenty of retro colour, and enduring appeal. It's a song nothing like many of the electronic based chart toppers of 2014, but it's rich, compelling, and emotional.
Neilson gave a wonderfully enthusiastic thank-you speech as she accepted the award from last year's winner Lorde, acknowledging her husband for helping her continue to write and record and tour, despite having two small children, and even managed to include a couple of jokes about breastfeeding.
Last year's Silver Scroll winners Ella Yelich-O'Connor, aka Lorde, and her co-writer Joel Little, took home two more awards this year, being awarded the Most Performed Work In New Zealand for the song Team, and the Most Performed Work Internationally for Royals. Little was also a finalist this year for his work with Broods.
The APRA Maioha Award was won by Robert Ruha for his song Tiki Tapu, while the SOUNZ Contemporary Award was won by Michael Norris for Inner Phases.
And in a new section of awards, Victoria Kelly won the award for Best Original Music in a Feature Film for her work in World War I television feature Field Punishment No 1, and Tom McLeod won the award for Best Original Music in a series for his work on the second season of Girl vs. Boy.
The night also saw late classical and electronic music pioneer Douglas Lilburn inducted into the prestigious New Zealand Music Hall of Fame, and honoured with speeches and performances from a wide range of the musical community.
The awards ceremony was marked by innovative cover performances of all the nominees works by fellow Kiwi artists, under the musical direction of the Phoenix Foundation's Lukasz Buda.
Performers included a gamelan orchestra, a choir, and a mind-bending electronic soundscape, along with acts like Estere, Electric Wire Hustle, and The Golden Awesome.
