In a few weeks, jurors will decide if Led Zeppelin lifted the guitar intro to “Stairway to Heaven” from an instrumental song “Taurus” by the California psychedelic pop-rock band Spirit. Three of the former members of Spirit live in the Houston area.

The suit was filed in 2014 by original Spirit bassist Mark Andes and the estate of “Taurus” composer Randy Wolfe, known in his Spirit days as “Randy California,” a handle bestowed upon him by none other than Jimi Hendrix. After leaving Spirit, Andes held down the bottom end for Jo Jo Gunne; soft-rockers Firefall; and then, during their chart-topping 1980s run of pop hits, Heart. After leaving Heart, Andes moved to Austin with one-time love interest Eliza Gilkyson and stuck around after their relationship ended. Since then he has married and now lives in Montgomery County, just north of Houston. Citing the ongoing suit, Andes politely declined to comment.

Houston is also the home of Austin-bred brothers Al and John Staehely, both of whom played in Spirit after Andes’s departure and the composition of “Taurus.” Al Staehely is now Houston’s most prominent entertainment lawyer.

Back to the suit. If you haven’t done so already, listen to the two songs back-to-back:

Zeppelin guitarist Jimmy Page and singer (and former Austinite) Robert Plant, composers of “Stairway,” are the defendants. The suit seeks to have Wolfe listed as a co-composer alongside Page and Plant, who have long claimed to have written the song in the stark, rustic confines of Bron-Yr-Aur, an isolated Welsh cottage, near where the faeries gambol and the hobbits frolic.

The Zep camp has long maintained silence on the suit. They have experience in these matters; Zeppelin have long been branded musical magpies, and have the courtroom reversals to prove it. In the early 1970s, Chester Burnett, the gravel-voiced Chicago bluesman known as “Howlin’ Wolf” successfully won partial songwriting credit for Zeppelin’s “The Lemon Song” thanks to its close resemblance to his song “Killing Floor.” About ten years later Willie Dixon, another Chicago blues legend, sued the band over their appropriation of elements of his “You Need Love” in their “Whole Lotta Love,” eventually winning his own partial credit. In the 1980s, folksinger Anne Bredon got a partial credit for her “Babe,” which Page recast as Zep’s “Babe I’m Gonna Leave You.” And only four years ago, folksinger-turned-jingle composer Jake Holmes settled with the band over their alleged appropriation of his “Dazed and Confused” for their own, well, you know already. In 2012, a Zeppelin album appeared with the composition of “Dazed and Confused” credited to “Jimmy Page, inspired by Jake Holmes.”

In a filing leading up to that development, one of Page’s lawyers attempted to win a dismissal of Holmes’s suit on the grounds that his version of “Dazed and Confused” “lacks originality and is thus not protectable by copyright.” That card could once again come into play this time around, as there is a third, earlier song that sounds very much like these two. (More on that later.)

People for whom I’ve played “Taurus” and “Stairway” have shown what to me is a surprising amount of division in their opinions. To my non-musician ears, and those of several other non-players, the two songs sound strikingly, uncannily alike. Trained musicians, on the other hand, tell me things like “the fingerpicked A-minor arpeggio is similar, but does not have the ascending melody on the high E-string,” and “you cannot copyright a chromatic scale and a single chord which is what Spirit is trying to do.”

In light of the recent “Blurred Lines” ruling, that last statement seems like wishful thinking. In that case, the estate of Marvin Gaye persuaded a jury that the Robin Thicke/Pharrell-penned smash simply lifted the groove and all-around vibe of Gaye’s “Got to Give It Up.”

“Sounds like” did in fact equal copyright infringement, and, indeed, “sounds like” forms about half of what a plaintiff needs to prevail in a case like this. It can’t just be a passing resemblance though; a jury must believe that the two pieces are virtually identical. “Taurus” and “Stairway” sounded alike enough for Los Angeles-based federal judge R. Gary Klausner, who declined to dismiss the suit.

Also at issue in the upcoming trial will be access, a far more objective question than the “sounds like” factor. Can it be proven that Page or Plant heard “Taurus” (which was composed in 1966 or 1967 and released in 1968) before they released “Stairway” in 1971? Spirit seems to be in pretty good shape here. According to Bloomberg, Led Zeppelin’s very first show on American shores took place on December 26, 1968, in Denver, where they opened for, uh, Spirit. Andes has said that “Taurus” was a fixture of Spirit’s set at the time, and evidently his band had impressed the Brits enough for them to include another Spirit song in their live repertoire a mere four days later in Spokane, Washington, where Zep adapted “Fresh Garbage” in a medley that they subsequently performed at a minimum of eleven more shows on that tour.

The two bands shared bills in Detroit, Atlanta, Seattle, and at Lewisville’s Texas Pop International Festival over the next couple of months, sometimes following each other to the stage, other times, at festivals, a day apart. (Surviving members of Led Zeppelin say they did not listen to Spirit’s music at those festivals.) Add to that the fact that “Taurus” had long been available on LP by the time Zeppelin released “Stairway to Heaven.”

Based on that evidence, if I were a betting man, I’d wager that the jury’s eyes would glaze over as expert witnesses testified about declining chord progressions and arpeggios and the like, and it would come down to the layman’s interpretation. Does “Taurus” sound virtually identical to the intro of “Stairway”? Do they share the same quasi-mystical vibe, just as “Blurred Lines” and “Gotta Give It Up” bring substantially the same party to your ears?

I think so, but I am not on the jury.

And then there’s that third song I mentioned earlier, the one that could possibly be used to argue that “Taurus” lacked originality. Give a listen to British folk-jazz guitarist Davy Graham’s moody, bluesy, Spanish-tinged 1959 interpretation of the American torch song “Cry Me a River.”

Though little-remembered today, Graham was the UK’s first guitar god. The instrument caught on a little before rock and roll, and Graham was fascinated by roots musics like jazz and blues. To my ears, aside from the “Stairway”-like arpeggios on the intro, the overall vibe of this sounds like a straight rip from New Orleans-bred guitarist Lonnie Johnson, or maybe one of his duets with the Sicilian-American Eddie Lang.

Page would have been fifteen when that melancholy film aired on the BBC, and Graham’s recordings were widely available throughout his musical youth. That he could have escaped hearing Graham’s “Cry Me a River” is almost unfathomable to some.

“Davy Graham was the guitar player to steal from in early ‘60s England,” says music industry veteran Greg Ellis, currently the owner and manager at Austin’s Groover’s Paradise record store. “Page absolutely knew every note of whatever LP this was on. As for Randy, there’s a good chance his stepdad, Spirit drummer Ed Cassidy, would know Graham and have an album.”

By 1959, Cassidy was an established jazz drummer with contacts on both sides of the Atlantic. One of the artists Cassidy had backed was Julian “Cannonball” Adderley, whose “Sermonette” Graham covered on his 1963 album The Guitar Player, which also included a version of “Cry Me a River.” It’s possible Cassidy handed his gifted stepson a copy of that LP, and young Randy absorbed Graham’s descending opening chord progression.

So how about this (purely hypothetical) scenario? Maybe Cassidy did give his stepson a copy of The Guitar Player, and maybe, five years later, Randy did incorporate Graham’s intro into “Taurus,” whereupon Page heard it at his first American gig and it triggered latent memories of hearing Graham a decade before.  And then those memories came bubbling to the fore again when he and Plant secluded themselves in that windswept, fire-lit Welsh cottage a couple of years later, and “Stairway to Heaven” was born.

That seems to me the likeliest scenario in this particular case.  There is nothing new under the sun. All of us unconsciously plagiarize every day, mostly in conversation. We pick up the verbal flourishes and turns of phrase of our friends and partners. Likewise, musicians pick up the riffs and licks of other musicians, sometimes blatantly and other times subtly.

Unlike “Stairway to Heaven,” though, our verbal flourishes and turns of phrase don’t tend to generate $562 million in revenue, and so we have copyright laws, and the way those laws are written, it certainly appears that Spirit has a decent shot in court.

Shortly before his death in 1997, Randy California had this to say: “I’d say it was a ripoff. And the guys made millions of bucks on it and never said ‘Thank you,’ never said, ‘Can we pay you some money for it?’ It’s kind of a sore point with me. Maybe someday their conscience will make them do something about it.”

But is this a matter of conscience or conscious?