Gaskell has more than 30 years experience as a legal academic, and most recently held the position of David Jackson Professor of maritime and commercial law at the University of Southampton School of Law in the UK. He was also the head of the school between 2003 and 2007, and the director of its Institute of Maritime Law between 1996 and 1999.

Gaskell has expertise in the areas of commercial, contract, international trade and maritime law, and has lectured widely on maritime law to the maritime profession and academic community throughout Europe, and in countries including China, Pakistan, Japan, South Africa, Singapore, Korea and New Zealand.

He is also a prolific author in the field of maritime law, and has participated in diplomatic conferences responsible for drafting international maritime law conventions.