Spider-Man, Captain America, and Tony Stark. Not only are these three guys some of the most popular characters in the MCU, they're also just three of the Marvel superheroes who deserve jail time for crimes committed throughout their respective filmographies.
Whether they're acting as members of the Avengers or going at it alone, the heroes of the MCU commit criminal acts that would put normal people behind bars for the rest of their lives. In some cases, these heroes are worse than the supervillains they're trying to stop.
Pretty much every hero in the MCU should be wanted for destruction of property and obstruction of justice. These films contain beloved characters who commit heinous offenses like homicide, reckless experimentation with A.I., and, uh, resisting arrest. The lawlessness is indisputable. It's almost remarkable that Endgame didn't finish with one long trial to put every one of these "heroes" behind bars.
- Photo: Avengers: Endgame / Walt Disney Studios Motion Pictures
Of all the heroes in the MCU, Hawkeye (or Clint Barton, if you prefer) is the character with the longest rap sheet. As an agent for S.H.I.E.L.D, Barton carries out dirty deeds the rest of the secret military operation doesn't want to handle - but as a member of the government, his assassinations are technically legal. It's when he gives up his government allegience following the events of Infinity War that he becomes a straight up criminal.
No longer an Avenger or a master archer for S.H.I.E.L.D, Barton is just going from country to country wiping out anyone who has anything to do with Thanos. Sure, he's technically going after "bad guys," but aren't they afforded the same level of due process as anyone else? And it's not like the ends justify the means; none of his hits as Ronin accomplish anything aside from making him feel better (although, all that bloodshed can't make him feel good).
Tallying up Barton's body count is a futile exercise; there are just too many corpses left in his wake.
- Photo: Ant-Man / Walt Disney Studios Motion Pictures
After he's released from prison at the beginning of Ant-Man, Scott Lang is faced with the issue of paying back child support; unable to get a real job thanks to his record, he pretty much immediately turns back to crime. Working with his happy-go-lucky former cellmate, Luis, Lang starts cracking safes and steals the Ant-Man suit.
As if breaking parole weren't enough, Lang continues breaking the law by escaping from jail with the use of his suit in the same film, joining a group of renegade Avengers to work as a domestic terrorist (or at least commit terrorist-ish acts), and then break out of his house arrest to enter the quantum realm with days left on his sentence.
- Photo: Thor: The Dark World / Walt Disney Studios Motion Pictures
The Battle of Greenwich is one of the most destructive, knock-down, drag-out fights you'll find in the MCU, and it turned much of London into rubble - all in the name of stopping Malekith and his dark elves from destroying the realms and rebuilding them in their vision.
Thor fights Malekith and his minions across the realms, jumping from portal to portal into worlds like Svartalfheim and Jotunheim, only to end up back in Greenwich to pile on the punishment of this formerly charming part of London. To make matters worse, Thor unwittingly brings a frost beast to Earth and just leaves it there to carry on with its animalistic destruction.
- Photo: Spider-Man: Homecoming / Sony Pictures Releasing
Depending on the day and the whims of Tony Stark, Peter Parker is either a junior member of the Avengers, or he's working freelance. When he's patrolling Queens and Manhattan on his own, without the blessing of Stark and his government contacts, Parker is essentialy carrying out vigilante justice.
There are a few instances in which his unchecked vigilantism errs on the side of the law. Stopping small-time bank robbers with out-of-this-world tech is one thing, but tracking and stalking a local contractor like Adrian Toomes across state lines is a whole other issue. Even if Toomes is trafficking Chitauri arms, that's not really something one super-powered teen should be worried about; he should leave stuff like that to government agencies like S.H.I.E.L.D.
On top of the whole stalking thing, Parker should be detained for obstructing justice after evading local Washington, D.C. authorities following the explosion of a Chitauri grenade. It's one thing after another with this Parker kid.