Smart contracts have tamper-evidence features that detect and prevent tampering, ensuring the integrity of the contract and its data. This includes:

1. Immutable code: Smart contracts are deployed on a blockchain, making their code immutable and unable to be altered.

2. Hash functions: Smart contracts use hash functions to ensure data integrity, making it difficult to alter data without detection.

3. Digital signatures: Smart contracts use digital signatures to verify the authenticity and ownership of data and transactions.

4. Consensus mechanisms: Smart contracts rely on consensus mechanisms, such as proof-of-work or proof-of-stake, to ensure that the contract's execution is validated by the network.

Tamper-evidence features provide several benefits, including:

1. Data integrity: Smart contracts ensure that data is accurate, complete, and untouched.

2. Contract integrity: Smart contracts ensure that the code and execution are unchanged and tamper-free.

3. Trust: Tamper-evidence features foster trust among parties, knowing that the contract and data are secure.

4. Compliance: Smart contracts can ensure regulatory compliance by maintaining an immutable and tamper-evident record of transactions and data.

By detecting and preventing tampering, smart contracts ensure the integrity of the contract and its data, creating a secure and reliable foundation for decentralized applications.