Factual error: The radio amateur uses the Revox tape recorder "B77" to record the radio conversations. This model came on the market in 1977, and the film is set in 1971.
Factual error: Michael X said that he was going to Trinidad to "liberate his people." This is rather misleading and gives the impression that Trinidad was still a British colony. Trinidad and Tobago gained its independence from the United Kingdom on 31 August 1962 so whatever people he had there were already liberated. Also, when the MI5 agent went to Trinidad to check the whereabouts of Gale Benson, he should not have had the power to order the police to burn down any building as Trinidad and Tobago is not subject to the powers of The Crown.
Suggested correction: This is not a mistake. It is based on real-life events. He means that he wants to liberate his people from oppression, as there was still an atmosphere of racism throughout the British colonies.
Revealing mistake: When they demo (and drop) the thermal lance, a wooden table flips on its side in the chaos. Immediately afterwards you can see a linear actuator they used to flip the table attached to one leg.