(CNN) -- Supporters of jailed Ugandan opposition leader Kizza Besigye plan to question Ugandan President Yoweri Museveni on Besigye, as well as Museveni's dedication to democracy, during the Commonwealth Heads of Government meeting Museveni is attending in Malta, a spokesman said Friday.Supporters of Besigye's Forum for Democratic Change (FDC) will ask Museveni about his "commitment to democratic principles and free press," said Sam Akaki, a London-based FDC spokesman.Besigye was arrested in October, and on Thursday was "dragged before a military court and charged with treason," Akaki said.At the time of Besigye's arrest, Maj. Gen. Kale Kaihura, Uganda's police inspector general, told CNN authorities had "collected evidence linking Besigye to the People's Redemption Army, which is being organized to overthrow the government of Uganda."Police have also collected evidence linking Besigye to another group, the Lord's Resistance Army, he said at the time.The arrest reportedly sparked protests in central Kampala, Uganda's capital city.On Thursday, Akaki said Besigye refused to answer the treason charge in the military court, prompting the chair of the tribunal to enter a not-guilty plea on his behalf. A military court trial is set to begin December 19.Besigye is expected to appear in High Court on Friday for a bail hearing. Although both the High Court and the military court have charged him with treason, it was unclear which would take precedence. Military courts typically handle alleged crimes committed by military members, and Besigye is a former Army colonel.Besigye returned to Uganda from exile in October. A runner-up in Uganda's 2001 presidential election, he maintains popular support in Kampala and Uganda's outlying areas.Besigye is considered to be Museveni's main rival in Uganda's upcoming presidential elections, to be held in March. Museveni has held power for 19 years."We are considering a boycott of the elections," Akaki said.The Commonwealth Heads of Government meeting, in Valletta, Malta, began Friday and will last through Sunday. Topics are expected to include poverty, international trade and world security.