When Katniss was little, she would blurt out bad things about the government. Her mom would worry so much because you can get severely punished for it. The government doesn't want people to make them look bad so they will even punish people by death.
Government doesn't care
You know, District 12 is suffering of hunger.
Oh, who cares.
The government chooses your job based on where you live, so you don't get to choose. It's always unfair because some jobs get paid more too. That's why some areas are nicer than others.
In the book, Katniss needs to leave to city, but the government doesn't allow people to leave. Some of them need to leave to survive, but there is a barbed wire fence that keeps everybody in. Luckily, because the area is so poor, the electricity is turned off, allowing Katniss to illegally leave.
Fear of the outside world
While everyone is struggling, the government just sits around. They don't care about the needs of the people, they just want them to look good. They also have nicer things and more food than the districts.
Every year, the Hunger Games are hosted.The Hunger Games are where the government forces kids to fight to the death because they have so much control. They do it to show everyone that they will always have power over them.
The government makes people believe that the outside world is dangerous and scary, when in reality, it's not scary at all. They use that to prevent people from leaving. The government just wants the people to stay in their sad, lonely dystopia.