Kikar is reporting that Rav Yitzchak Zilbershtein was asked about faking a donation on Purim.

The question asked was regarding people who come on Purim and request donations, but they do so in a very unpleasant way and keep adding pressure on the potential donor to give more and to increase his donation. The donor asked that he had already given a nice donation but they would not leave him alone and were pestering him to give more.

When he could not take it any longer, he took out his checkbook and wrote fake checks that would not be honored by the bank when deposited, as he scribbled the signature differently than his own normal signature. Not realizing the check would not be honored, the collectors left happy with their windfall. The donor now feels bad about what he did and wants to know if it was ok or if he needs to at least pay the fee for trying to deposit a bad check - money he is causing them to lose, or if he would have to possibly even pay them more than that for the donation he sort of gave them but did not honor.

Rav Zilbershtein responded with a psak that a donor could do what he needs to do to get out of giving more than he is capable or willing to donate - even if it takes some deceit. If the collectors act improperly and pressure the donor to give money he is not obligated to give, the donor can also act with some deceit to get rid of them.