Undue Influence (Section 16, Indian Contract Act, 1872):

Undue influence occurs when the relationship between parties is such that one party is in a position to dominate the will of the other and uses that position to obtain an unfair advantage. It is a subtle form of coercion where consent is not truly free because it is obtained by exploiting a position of power or trust, rather than by direct threat.

Key Elements:

1. Dominant Position: One party must be in a position to dominate the will of the other. This can arise in several ways:
   • Real or Apparent Authority: E.g., employer over employee, police officer over accused.
   • Fiduciary Relationship: E.g., parent over child, guardian over ward, doctor over patient, solicitor over client, spiritual advisor over devotee. These relationships involve trust and confidence.
   • Mental or Bodily Distress: Where a person's mental capacity is temporarily or permanently affected by age, illness, or distress, making them vulnerable.
2. Use of Dominant Position: The dominant party must have actively used their position to influence the other party.
3. Unfair Advantage: The dominant party must have obtained an unfair advantage over the other party through this influence. The transaction must appear unconscionable or inequitable.

Presumption of Undue Influence: In certain relationships (e.g., parent-child, doctor-patient, spiritual advisor-devotee), the law presumes that undue influence has been exercised if the transaction appears unconscionable. In such cases, the burden of proving that the contract was not induced by undue influence shifts to the dominant party.

Effect: A contract induced by undue influence is voidable at the option of the party whose consent was so caused. The aggrieved party can choose to either uphold the contract or set it aside.

Fraud (Section 17, Indian Contract Act, 1872):

Fraud refers to any act committed by a party to a contract, or with their connivance, or by their agent, with the intent to deceive another party or their agent, or to induce them to enter into the contract. It involves a deliberate misrepresentation or concealment of material facts.

Acts Constituting Fraud:

1. False Suggestion of Fact: The suggestion, as a fact, of that which is not true, by one who does not believe it to be true. This is a direct lie about a material fact.
2. Active Concealment of Fact: The active concealment of a fact by one having knowledge or belief of the fact. This is more than mere silence; it involves deliberate efforts to hide information.
3. Promise Without Intention of Performance: A promise made without any intention of performing it. This relates to a future intention that is misrepresented at the time of making the promise.
4. Any Other Deceptive Act: Any other act fitted to deceive. This is a residuary clause covering various forms of deception.
5. Statutory Declaration of Fraud: Any such act or omission as the law specially declares to be fraudulent (e.g., certain provisions in the Transfer of Property Act).

Key Characteristics:

• Intent to Deceive: The most crucial element is the intention to deceive or induce the other party into the contract.
• Misrepresentation of Fact: The fraudulent statement or concealment must relate to a material fact, not merely an opinion.
• Reliance: The aggrieved party must have relied on the fraudulent statement or act and been induced by it to enter into the contract.
• Mere Silence: Generally, mere silence as to facts likely to affect the willingness of a person to enter into a contract is not fraud, unless there is a duty to speak (e.g., contracts of 'uberrimae fidei' or utmost good faith, like insurance contracts) or where silence is equivalent to speech.

Effect: A contract induced by fraud is voidable at the option of the party whose consent was so caused. The aggrieved party can also claim damages for any loss suffered due to the fraud.