Hello, I assume you are asking about Personal Safety issues while dating online. There are a few things you may want to consider in order to keep yourself safe online period not to mention when you are going to actually become involved with someone you meet through a dating site.
Part of the problem is it's anonymity. Anyone can portray themselves as anyone they wish to be. Don't confuse someone using a credit card to join a dating site with a security clearance, they are not the same thing.
The only thing that the dating site is authorized to do is check that there is enough money in the account to accomodate the charges and that is it. They have no real viable/legal means of conducting a security/criminal record check or to determine if the individual is a threat to others using the service other than what the subscriber puts into their profile. These checks can only be conducted by law enforcement, private investigators and the government.
Some of the warning signs that you may want to be aware of are the same signs that should give you pause when dating period.
#1 Be aware of anyone who has to be in control or in charge of everything. This is a good indicator of how this individual behaves in their real life as well as online.
#2 Understand that there is a huge risk involved in meeting anyone we don't really know. Set up your initial meetings in a public places. Let someone know where you're going, who you're meeting and when you expect to return. 60% of date rapes occur during the first 5 dates and are usually at the perpetrators home.
#3 Be wary of anyone who trys to get too much information from you or information that is not relevant or appropriate to the conversation at hand. Many predators are gifted interviewers and manipulators. Do your research into predator dynamics as well as dating violence and the criminal mindset.
#4 Be aware of individuals who attempt to use charm and guile to manipulate or control you. Being charming and nice is not the same thing as being a good person. These are social strategies we adopt to get what we want.
#5 Above all use good Personal Safety skills and trust your gut. Context in most things is usually what is important, not the words being spoken. If something doesn't feel right, it probably isn't don't second guess yourself.