Allegation

Allegation – noun

a statement saying that someone has done something wrong or illegal

Definition:
1:  the act of alleging

2: a positive assertion; specifically :  a statement by a party to a legal action of what the party undertakes to prove

3: an assertion unsupported and by implication regarded as unsupportable e.g. <vague allegations of misconduct>

Source:

http://www.merriam-webster.com/dictionary/allegation

Encounter:
I was reading a article on the New York Times about how evidence is often mishandled by the F.B.I. it was alleged that there were missing and mislabeled evidence which is certainly shady dealings. In this case its the idea that the F.B.I. may have been doing something wrong or illegal