The consequence for not seeking leave where a ground of appeal is of mixed law and fact is fatal to the ground. However, one ground of appeal on law in a Notice of Appeal, I must observe, is capable of sustaining an appeal but not otherwise in which case the Notice of Appeal as well as the grounds of appeal is incompetent and liable to be struck out. – Chukwuma-Eneh JSC. Yaro v. Arewa CL (2007)
Leave means permission. Where an appeal is not as of right, leave under section 233 (3) of the constitution is a precondition that an applicant/appellant must seek and obtain before his appeal is entertained. The appeal would be declared incompetent and thrown out if the applicant failed to fulfill the pre-condition.
– Rhodes-Vivour JSC. Nwaolisah v. Nwabufoh (2011)