The Winchester brothers from Supernatural are presented as all-loving heroes who fight monsters and cosmic beings to save people on Earth. However, there have been more than a few times where Sam and Dean intentionally made decisions that caused unspeakable death and tragedy, often in ways the show glosses over. Some of their worst acts can be attributed to Soulless Sam and Demon Dean, but even when they've been totally lucid, the brothers have straight-up ignored dangerous consequences to fit their own needs, valued their own lives over those of many others, or just blatantly didn't help people they easily could have.
Here are times when Sam and Dean were basically villains.
Dean Ganks Sam's Friend Amy And Leaves Her Son An Orphan
Sam's friend Amy was a Kitsune, a creature that feeds on people's brains. She saves Sam's life by slaying her own mother. As adults, Sam tracks Amy down after she's been feeding on people. He lets her go due to Amy once saving his life, as she promises to stop and because she only did it to save her son's life when he was very ill and needed to be fed.
Unfortunately, Dean tracks Amy down and ganks her anyway while her son watches. He doesn't care to see what will become of the orphan, and even threatens the boy that he'll be next if he becomes like his mother. Then, he just leaves the boy alone and motherless.33457Pretty evil?
They Let Adam Remain In Hell For 10 Years
Adam is possessed by the archangel Michael and is pulled into Hell when Sam throws himself into Lucifer's cage to seal the devil with himself. While Dean convinces Death to save Sam, he doesn't try to rescue his other brother.
In Season 15, it's shown that Sam and Dean can enter the cage at any time by requesting that the Ruler of Hell open the passage, which means they let Adam remain in Hell for more than 10 years on purpose. The brothers always argue that family comes first, but this is their own brother that they abandon in Hell when they could've easily rescued him at any time.30867Pretty evil?
They Trap Jack In The Ma'lak Box After He Gives Up His Soul For Them
Jack loses his soul to end Alternate Michael's life and save the Winchesters. Rather than accept that the malevolence he exhibits afterward is because he doesn't have a soul and can't understand emotions anymore, Dean swears vengeance when Jack accidentally takes Mary's life after she pushes him too far. He then convinces Sam to trap Jack forever in the Ma'lak box, lying to Jack that they will cure him.
Jack became soulless for Sam and Dean, but the two have no care for his sacrifice and attempt to seal him till the end of time when they could have tried to get his soul back instead.26857Pretty evil?
They Plan To Manipulate And Kill The Innocent Amara
Amara changes her ways after she realizes that humans and creation are beautiful things that need to be preserved. However, Dean devises a plan to capture Amara and end her existence because she balances the power of the universe, and since they intend to take out Chuck, Amara also has to perish.
Amara is essentially innocent and hasn't done anything to deserve this fate, but Dean convinces Sam to go along with finishing Amara's existence. He makes it worse by outright lying to Amara that he won't hurt her when he really hopes to wipe her out once she's captured.24251Pretty evil?