Why did the Securities & Exchange Commission Sue Kraken?

Could you elaborate on the reasons behind the Securities and Exchange Commission's decision to sue Kraken? I'm particularly interested in understanding if it relates to any potential regulatory violations or market misconduct. Was there a specific incident or pattern of behavior that prompted this legal action? Furthermore, what are the potential consequences for Kraken if they are found guilty, and how could this lawsuit impact the overall cryptocurrency and financial landscape? It's crucial to gain clarity on these issues in order to fully understand the gravity of the situation.