The constitutions of most colleges in Scotland incorporate the Further and Higher Education (Scotland) Act 1992, which gives ministers a number of controls over them, including the power to remove trustees, close or merge colleges, and force management boards to comply with specific requirements.
Ministerial consent is also required for colleges wanting to borrow money, sell property or amend the powers of their management boards.
Ryder said ministers needed to either give up their powers over colleges or change the law to exempt further education institutions from the provisions of the 2005 Charities Act.
Ryder said: "If we don't make any change colleges will fall foul of section seven [of the act]. Therefore, a decision needs to be made."