I can no longer trust my PI after his handling of authorship. What are my options?
Your Situation

The restrictions placed by your lab are part of the working conditions under which you operate.  This includes the personality and working culture of your colleagues and superiors.  This is difficult and slow to change, and will impact you regardless of your own actions.  Trying to avoid conflict with this culture will let you get on with your own work, until such a time that you see a better option to follow.  If you can't tolerate this, then consider one of the following options:

Your Options


Call another meeting with your PI.  State the matter of record, that he
already called you to offer you first authorship.  Request that your PI honour this offer.  He then has the opportunity to agree with you and give you recognition, or to contradict both your wishes and his agreement.  If his actions result in a negative outcome for you, then you can record this for possible further use such as a complaint.  Ensure that your actions at all times reflect your professional integrity.  This option may help to establish the boundaries around which you are prepared to operate within the lab.
Conduct an appeal for help with an agency outside of your lab.  Is there an ethical or professional support group that you can contact?  Provide the details of your case, and request assistance in investigation and documentation of the issue.  This is an avenue which could lead to cultural change within your lab, but potentially at a personal and professional cost to you.  It could possibly lead to you needing to leave the university.
Begin discussions with other experts at your university to identify
opportunities for your career within the same university.  Ensure that there is no further escalation of conflict with your PI.  Try to smooth over the differences within your lab.  its important that this issue does not have a negative impact on your transition to a new group.


General Advice

I suggest that you consider taking professional advice from a senior researcher who is prepared to act as a mentor for you.  This would allow you to discuss issues, and to increase awareness of your career opportunities and research strategies that you will need throughout your career.