In Captain America: Civil War,
The Avengers are split on whether to sign the Sokovia Accords.
On the side in favor are
The Vision, Black Widow, Iron Man, War Machine, Spider-Man (kinda),
On the side against are
The Scarlet Witch, Falcon, Hawkeye, Captain America, Ant-Man, and the Winter Soldier, and later the Black Panther
When Captain America and
seek to escape in order to stop Baron Zemo, the other three members of their group are taken into custody, and imprisoned
by the United Nations on a submarine.
Now, most of these people are essentially powerless without their gadgets, and could be contained quite readily by a normal prison. By contrast,
Wanda the Scarlet Witch is very powerful, able to summon up enough force to throw the Vision through several dozen floors and into the ground. Even Bucky Barnes, with his mechanical arm, was able to punch his way out of the similar prison that he was contained in earlier—and he doesn't have much on Wanda. This doesn't even take into account her ability to control the minds of her captors.
How was the prison able to contain someone with that power set?