Synonyms for Allege:

n.

bring before, prefer charges (against someone), bring someone up on charges of something. argue, avouch, hold, contend. law, lay, words, present. allege (noun)
say, aver.
assert (noun)
testify.

v.

accuse (verb)
condemn, inculpate, impeach, impute, denounce, charge, criticize, cite, incriminate, blame, implicate, arraign, complain, reproach, accuse, scold.
assert; claim (verb)
cite, lay, charge, plead, avouch, testify, present, aver.
communication (verb)
say, aver.
plead (verb)
beg, excuse, plead, justify.
pleading (verb)
Begging.
sue (verb)
subpoena, indict, litigate, prosecute, sue, summons.

Other synonyms:

bring before, avouch. contend, argue. lay. hold. accuse
litigate, indict.
Other relevant words:
hold, contend, aver, avouch, say, present, lay, words, law, testify, argue.