Joni Mitchell fell in love with jazz as a teenager—in particular, the sound of Miles Davis’ trumpet. “Miles Davis taught me how to sing,” she said onstage in 1974. “Pure straight tones holding straight lines. The feeling when you sing and you open up your heart.” As much as we call her a folk singer (her acoustic guitar, her historical context), her music always felt more like jazz whether it sounded like it or not: the subtlety, the complexity, the privileging of personal freedom over the unity of (and accessibility to) the crowd. You could sing Neil Young at a protest or a campfire; Joni Mitchell, not so much. Joni’s Jazz, which starts with 1971’s “Blue” and goes on to present a non-chronological edit of album, live and demo tracks going all the way up to “Summertime” from the 2022 Newport Folk Festival, is both a celebration of her music and an argument of sorts about it—namely that the “jazz” that drove the narrative around definitive but divisive albums like 1975’s The Hissing of Summer Lawns and 1979’s Mingus was actually a central part of her sound for most of her career and a driver of her creative legacy. (Of Hissing, she once joked that she “cut the jazzers some slack…and that was the kiss of death.”) The irony of this progressive, often wild music is that it came out of a rejection of what at the time was considered cool. “I couldn’t get anybody to explain how this got to be hip,” she once said of her frustrations with the recording process in the late ’60s. “It wasn’t as good as the sound that went before.” Basic stuff, she meant—how drums sounded, the way a bass player arranged their part around her vocal melodies. “They would get exasperated, like I was ignorant,” she said. “Until one guy said, ‘Joni, you’re gonna have to play with jazz musicians.’” There’s an idea.