I doubt it. Public pension fund portfolios are full of more speculative investments than ARIA (e.g., VC, highly leveraged commercial real estate). Also for the most part they make investments through advisors, mainly for their expertise but partly to shield them from blame when things go wrong.
That said public pension plan officials are notorious for a different type of breach of fiduciary responsibility - feathering their own nests at the expense of benificiaries. This type of activity tends to get a lot of press.
A pension plan can invest in anything they want. The investment manager has the responsibility to invest in accordance with the investment guidelines determine by what ever fiduciary body oversees the plan. However that oversight body can set the guidelines for allocation. I've seen plenty of pension plans have investment guidelines that allow for investment in far more speculative assets than ariad. iE private equity funds. Not sure where you are getting this conspiracy theory from. Either way even if the fund gets sued that has zero impact to ariad now. So what's the point?