Ask Father: I Discovered That the Hosts Used Are From Flour of a Variety of Grains. What to Do?

Father Zed address a VERY serious question with sound, practical advice.

From Fr Z's Blog

From a reader…
QUAERITUR:

I recently discovered that the priests at a chapel I had been attending have been using bread made of flour from a variety of grains, so it’s clearly invalid. The chapel is run by religious order priests. (You can probably guess the order.)

I think I need to report this, but I don’t really know how to do that.
Do I write a letter? To the bishop himself or to a particular office?
To the superior of the religious order? What do I say in the letter?

Should I include a litany of all the liturgical abuses I observed, or keep it to the more serious ones? What should I expect after the letter is received? etc.

If you’re willing, I’m also interested in the broader question: What is my duty as a lay person in such circumstances? I honestly don’t expect that anything will change, but I owe my due diligence. What is my due diligence?

This is serious issue.
If the bread used for the Mass was invalid substance, because it was not from wheat flour, then Masses using that bread weren’t Mases at all.  Furthermore, that means that the Precious Blood was consecrated outside of Mass.
Moreover, that means that all those stipends and Mass intentions were not, in justice, fulfilled!   How many Masses?!?
If you have some sort of proof that the hosts were not of wheat bread make your concern immediately known in a BRIEF letter – including the evidence – posted to the local person in charge, with a copy to the local bishop and to the Apostolic Nuncio in Washington DC and/or the Congregation for the Doctrine of the Faith.   There are stipend/intentions issues involved that they must solve.
If you have strong suspicion of the same, then write the letter to the local person in charge, with a copy to the local bishop, asking for clarification about the hosts.
What are your responsibilities in this matter?
I refer you to the important CDW document Redemptionis Sacramentum.

6. Complaints Regarding Abuses in Liturgical Matters

[183.] In an altogether particular manner, let everyone do all that is in their power to ensure that the Most Holy Sacrament of the Eucharist will be protected from any and every irreverence or distortion and that all abuses be thoroughly corrected. This is a most serious duty incumbent upon each and every one, and all are bound to carry it out without any favouritism.

[184.] Any Catholic, whether Priest or Deacon or lay member of Christ’s faithful, has the right to lodge a complaint regarding a liturgical abuse to the diocesan Bishop or the competent Ordinary equivalent to him in law, or to the Apostolic See on account of the primacy of the Roman Pontiff.  It is fitting, however, insofar as possible, that the report or complaint be submitted first to the diocesan Bishop. This is naturally to be done in truth and charity.

You have the right and duty to make your concerns known in this important matter.  You always have the right to immediate recourse to the Holy See.  However, you can, and should, inform the local bishop.

Try to get things solved at the lowest level possible and work your way up.

Keep all your communications brief and respectful, on one side of sheet of paper if possible.  Include proofs, evidence, not guesses.   In the case that something is not 100% sure, ask for clarifications.

Read this about writing to ecclesial authorities.

Tips for writing to the Vatican, bishops and priests