The figure does not include the estimated ?1 million the firm claimed for representing Hamza. The firm's figures have gone up steadily as the war on terror has progressed.
Politicians and public spending watchdogs have condemned the huge sum, which met by the taxpayer.
Matthew Elliott, the director of the Taxpayers' Alliance, said: "Ordinary people are sick of legal aid being wasted on those who openly hate Britain. When the concept of human rights is twisted by highly paid lawyers to protect such people, it undermines trust in our justice system."
The firm Arani & Co, run by Ms Arani, 42, became synonymous with Hamza as he fought extradition to America, and then prosecution for racehate crime.
The law firm states it specialises in fighting "abuses taking place as a result of the so-called alleged war on terror" and is based in a small office above a cash-and-carry in Southall, Middlesex.
Details of Arani & Co's latest earnings were released to the Daily Express under the Freedom of Information Act.
The news comes as ministers are trying to shave &?100 million from the annual ?2.1 billion spent on criminal and civil legal aid.