The term 'fair and equitable treatment' is a flexible and, therefore, imprecise term which is found in many bilateral investment treaties (BITs). Notwithstanding the imprecision of the 'fair and equitable' term in BITs, it is thought to include a breach of the 'denial of justice' standard. But, even if 'denial of justice' is not within the concept of 'fair and equitable' treatment found in BITs, 'denial of justice' is a principle of customary international law and, therefore, applicable in investor claims. Please discuss the respective meanings of 'fair and equitable' treatment, and 'denial of justice' separately and in conjunction with each other, and explore the process by which an investor can claim for breach of 'denial of justice' under a BIT or, in the alternative, in customary international law.

Please support your response by reference to appropriate published sources.