Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE claims_processing ( claim_processing_id number, claim_id number, claim_outcome_code text, claim_stage_id number, staff_id number )
TABLE: CREATE TABLE claims_documents ( claim_id number, document_type_code text, created_by_staff_id number, created_date number )
TABLE: CREATE TABLE customers ( customer_id number, customer_details text )
TABLE: CREATE TABLE staff ( staff_id number, staff_details text )
TABLE: CREATE TABLE claims_processing_stages ( claim_stage_id number, next_claim_stage_id number, claim_status_name text, claim_status_description text )
TABLE: CREATE TABLE policies ( policy_id number, customer_id number, policy_type_code text, start_date time, end_date time )
TABLE: CREATE TABLE claim_headers ( claim_header_id number, claim_status_code text, claim_type_code text, policy_id number, date_of_claim time, date_of_settlement time, amount_claimed number, amount_piad number )

### Question ###
Find the names of the customers who have an deputy policy.

### Accurate SQL ###

SELECT DISTINCT t2.customer_details FROM policies AS t1 JOIN customers AS t2 ON t1.customer_id = t2.customer_id WHERE t1.policy_type_code = "Deputy"