Legal Question in Construction Law in California

Obviously, this is wrongdoing. There are various legal actions that can be taken, including a legal dissolution of the partnership. The first place to start, however, is with the partnership agreement if there is one in writing. It may provide a process for dealing with disputes. The bank accounts should be changed to require two signatures or the money otherwise immediately controlled. Emergency relief can be requested from the court until a solution is worked out. Without knowing more, it is impossible to determine whether further action may result relating to the work for the competitor, but that is definitely something that should be considered. The actions taken to disrupt the business are likely actionable under unfair competition. Other than providing these generalized comments to confirm that there is a legal strategy available, it is impossible to provide a specific recommendation based on the limited information in your post. It would be necessary to review the partnership agreement and get additional information regarding the rogue partner's actions.