"How can you tell the difference between SM and abuse?"
To a casual observer SM and abuse can look very similar. They may both involve an element of humiliation and/ or result in bruises. It can also be very hard for someone on the receiving end of domestic violence to admit that there's a problem. One of the side effects of being abused is that it erodes your self confidence to the point where you believe that the violence is normal, or that you can cope with it on your own, or that somehow you deserve it.
It is even more difficult in an SM setting because the violence might have started off as a negotiated scene. Did the Top deliberately ignore your limits or did (s)he just misunderstand your signals? Abuse may occur outside of a pre-agreed scene but then be described as SM afterwards. Also the bottom may have pushed the Top further than they were willing to go.
So how can you tell the difference? I believe that SM is based on CONSENT. When consent is not given, or given under duress, then that is ABUSE.
Here are some other signs to look out for:
SM: The bottom has a safe word or knows that they can stop the scene as a last resort.
ABUSE: There is no way of stopping the scene, or safe words (if you are using them) are ignored.
SM: Everyone in the scene respects the needs, desires and limits of others.
ABUSE: Little or no concern or respect is given to the needs, desires and limits of others.
SM: Everyone in the scene is aware of the risks and has given consent while sober.
ABUSE: Alcohol and/ or drug use impairs the ability of players to set and respect limits. Afterwards substance use may be used as an excuse for abusive behaviour.
SM: It is clear when a scene ends and afterwards everyone involved feels positive about it, even if the scene itself was unsuccessful.
ABUSE: Beginnings and endings of scenes are unclear. Feelings of violation follow a scene that has turned into abuse.
If a full time Dominant/ submissive relationship is entered into (for example as 'Master' and 'slave') then any negotiation may be done at the start of the relationship, rather than before each scene. However, the Master still has a duty of care not to permanently damage the slave and the slave gives consent by remaining in the relationship.
Likewise, many advanced BDSM players or people who have played together for a long time do not use safe words. However, they are always reading the signals that a submissive is giving off, and know when they are pushing limits and when they should stop.
Sometimes an SM scene ends badly, perhaps through accidental injury or one of the players misreading the other one's signals. If this happens occasionally I would suggest that it's an accident and recommend that you discuss what happened to prevent it occurring again. If the cycle repeats itself several times then you might be looking at a pattern of abuse.
If you think you are being abused, are ignored when you ask your partner to stop during a scene, are afraid that your partner will punish you if you do want to stop, and/ or are afraid of your partner outside of a scene - you are not alone. Help is available. Please talk to someone. It could be your local Gay and Lesbian centre or switchboard, a domestic violence helpline or community leader. Your silence helps the abuse to continue. It doesn't have to be that way.
Thanks to the Howard Brown Health Center in Chicago for their help with this answer.
Have fun, and look after yourselves and the people you play with.
John Pendal
International Mr Leather 2003