Director Spike Lee has some passionate thoughts about Colin Kaepernick's career

Famed film director Spike Lee thinks something "smells mad fishy" about the fact that onetime San Francisco 49ers quarterback Colin Kaepernick, who is now a free agent, has remained unsigned in the NFL.

In a lengthy Instagram post Sunday, Lee called out NFL teams for not picking up the quarterback who became notorious last season for kneeling during the national anthem. Playing for the 49ers at the time, Kaepernick launched a movement of protesting the national anthem for what he saw as the alleged oppression of minorities in the U.S.

Just Had Brunch With My Brother Colin @Kaepernick7 . How Is It That There Are 32 NFL Teams And Kap Is Still A Free Agent? WTF. Smells MAD Fishy To Me,Stinks To The High Heavens. The New York J-E-T-S Need A Quarterback. Who Is The J-E-T-S Quarterback? Is My Man Joe Willie Namath Coming Back? Crazy Times We Live In. The Question Remains What Owner And GM Is Going To Step Up And Sign Colin So Their Team Has A Better Chance To WIN? What Crime Has Colin Committed? Look At The QB's Of All 32 Teams. This Is Some Straight Up Shenanigans,Subterfuge, Skullduggery And BS. Ya-Dig? Sho-Nuff. By Any Means Necessary. And Dat's Da NoFunLeague Truth,Ruth.

A post shared by Spike Lee (@officialspikelee) on Mar 19, 2017 at 2:10pm PDT

While Kaepernick's protest elicited a variety of responses — from praise to condemnation — Lee defended the football player Sunday.

"How is it that there are 32 NFL teams and is still a free agent," Lee posted on Instagram, adding the acronym WTF. "Smells mad fishy to me, stinks to the high heavens."

Lee suggested that the New York Jets should sign Kaepernick, a six-year veteran, since they "need a quarterback."

"Crazy times we live in," Lee wrote. "The question remains what owner and is going to step up and sign Colin so their team has a better chance to win? What crime has Colin committed?"

"This is some straight up shenanigans, subterfuge, skullduggery and BS," Lee said.

As Sporting News reported, Kaepernick's protest caused many NFL fans to boycott games and products from league sponsors. And there is a rancorous debate about whether Kaepernick's protest actually hurt the NFL.

Kaepernick, 29, has said that he plans to stand for the national anthem this year — should he be signed to a team. According to ESPN, Kaepernick said his protests garnered a national discussion on inequality, thus achieving his goal.

But some sports reporters and commentators, including Bleacher Report's Mike Freeman, have speculated that Kaepernick remains unsigned because of his activism.

Lee — known for his films that have explored race relations and urban issues — posted the Instagram photo after having brunch with Kaepernick in Manhattan's Little Italy, he said.