If we look at the game-by-game three stars data from the Pens' 2016 playoff run, Crosby was the leader. He had the most 1st star selections, the most total selections, and (if you use a 3-2-1 weighting) he had the most total points:
Player | 1st | 2nd | 3rd | Total | "Points" |
Sidney Crosby | 3 | 1 | 3 | 7 | 14 |
Matt Murray | 2 | 2 | 1 | 5 | 11 |
Phil Kessel | 1 | 3 | 1 | 5 | 10 |
Evgeni Malkin | 1 | | 3 | 4 | 6 |
Matt Cullen | 1 | 1 | 1 | 3 | 6 |
Patric Hornqvist | 2 | | 1 | 3 | 7 |
Nick Bonino | 2 | 1 | | 3 | 8 |
Kris Letang | | 2 | 1 | 3 | 5 |
Conor Sheary | 1 | 1 | | 2 | 5 |
Bryan Rust | 2 | | | 2 | 6 |
Carl Hagelin | | 2 | | 2 | 4 |
Chris Kunitz | | | 1 | 1 | 1 |
Jeff Zatkoff | | 1 | | 1 | 2 |
Eric Fehr | | 1 | | 1 | 2 |
Data has been taken from pnep's spreadsheet -
link
Given that the writers who watched the 2016 playoffs unfold ranked Crosby first, looking at the game by game results, it's tough to argue that there was a conspiracy to give him the trophy. (Unless someone is suggesting that multiple writers in five different cities are part of the conspiracy?)
(EDIT - I also took a look to see if Crosby got more three star selections in home games, as it can be argued that Pittsburgh writers would be biased to choose him. He was named one of three stars in 4 road games vs 3 home games, which isn't what you'd expect, if Pittsburgh writers were making a concerted effort to give Crosby undue recognition. In the three home games where Crobsy was named one of the three three stars, all of them look legit - there's a 3 point night, a 2 point night, and an OT goal).
(For what it's worth, even though he didn't do great in the three star voting, I probably would have voted for Letang. He played the best hockey of his career that spring. In any case, there was a clear top four, and any of Crosby, Letang, Kessel and Murray could have validly taken the Conn Smythe).