Before I respond to your inquiry, I must state that we have not spoken, I have not reviewed the relevant documents and facts, and I do not represent you. Therefore, my discussion below is not a legal opinion, but is informational only. Finally, my discussion applies only to issues to which Pennsylvania, New Jersey or Federal law apply, unless otherwise specified.
That being said, if anyone, whether a party or not, attempts to tamper with a witness, it is a crime. If the party acts through a third party, they are still liable. The issue is proving that they did so. You would likely need the witness to testify about the tampering attempts, or have other proof of the attempts. Threatening the witness with a lawsuit might be OK, if there is a good faith basis for the lawsuit, and the threat isn't "Don't testify about case A and I won't sue you about issue B." - that would be extortion.
The two solutions are (a) file a motion in your case for discovery or evidentiary sanctions (which will help your case, and possibly spark the judge to report the tampering to the DA) and (b) file a complaint with the police. I recommend speaking with an attorney first to assist you in navigating the issues.
/Christopher E. Ezold/
The Ezold Law Firm, P.C.
One Belmont Avenue,
Suite 501
Bala Cynwyd, PA 19004
(610) 660-5585
[email protected]
www.ezoldlaw.com