I believe that Johnny Manziel should be fired from the NFL because he has proven, time and time again, that he cannot control his alcohol abuse issues. Because Johnny is a popular sports athlete who is admired by many young and impressionable fans who may want to emulate his behaviors, he has a higher obligation to conduct himself properly, both on and off the field.
If Johnny Manziel is allowed to remain in the NFL regardless of whether or not he remains sober, it sets a poor example for the viewers and other players and casts the NFL in a bad light. Allowing him to remain without requiring him to stay sober makes it look like the NFL condones drunkenness and tells everyone loud and clear that if you have enough money and power, the rules don't apply to you.
Yes, Johnny Manziel should be fired from the NFL if he cannot stay sober. Manziel is a role model for younger people who idolize football players. One who has severe substance abuse problems and who refuses treatment should be fired so that young people see and understand that there are personal consequences that can happen when people are addicted to drugs.
Johnny Manziel is over 21 therefore it is legal for him to consume alcohol. He shouldn't be fired from the NFL because of his drinking alone. Now if his drinking affects him attending practice or at team activities then he should be fired. Although he gets carried away sometimes it is not illegal for him to be drinking.