There have been many debates in this forum as to what constitutes "griefing". It is not an official term, but rather a style of game play that players often complain about or object to. There are three schools of thought. They are:
1. Killing players does not constitute "griefing" because the game mechanics allow this.
2. Killing players can constitute "griefing", but only if this breaches the EULA which prohibits the "harassing or bullying of others" (c 7.3.1).
3. Killing players does constitute "griefing" if there is no legitimate in-game purpose or objective for the killing.
Each view has its pros and cons.
The first view is popular with proponents of P v P and has the fewest restrictions. Provided the killing of the player does not amount to harassment or bullying, then it is allowed even if it is a crime within the game. It is also the view adopted by FD at present. Even the proposed Pilots' Federation Bounty (PFB) and penalty re-buy mechanics do not seek to prevent the killing of players in any circumstances. At best may they be said to be game mechanics that discourage the killing of "clean" players in limited circumstances.
The second view is strict, and to my knowledge, has never been used. No doubt, if a player repeatedly killed another player for no apparent reason, then an argument could be made that this constitutes harassment or bullying contrary to the terms of the EULA, but this would be an extreme case. Using the ELUA also means that FD then has to deal with an in-game problem using an out of the game process. I suspect that is something FD is reluctant to do.
The third view is popular with players who engage in aspects of the game that do not involve P v P (such as exploration or trade). Most often the complaint is that they were killed for no apparent reason and in circumstances that were unfair (e.g. combat ship v trade ship). Unfortunately, what you or I think is unfair does not take the argument anywhere and most often ignites a debate about the attacking player's subjective intent, purpose, etc.
So all that can be confidently said is "griefing" does not have a precise meaning, but must amount to the harassment or bullying of a player within the meaning of the EULA before a ban will be imposed. In practical terms, this probably means that a player would need to target and repeatedly kill another player before FD steps in (if at all). That is not to say that the third view has no validity, but it lacks the precision needed to be regulated in game. The PFB and penalty re-buy is one way to regulate some forms player behaviour and the proposed karma system is another. However, none go so far as to prohibit the killing of players if the attacker is willing to accept the in-game consequences. That may be a bounty, large re-buy cost and bad karma, but not a ban.
In the end, the P v P catch cry "git gud or go solo" is the answer
P.S. This thread probably should be in the general discussion sub-forum as it really has little to do with the beta.