Months-long Guardian investigation exposes weaknesses in code of conduct that could trigger calls for greater reform

• Calls to toughen Lords rules as it is revealed one in 10 peers are paid for political advice
• What is the House of Lords and what do peers do?

A Guardian investigation into the House of Lords raises questions over the accountability of parliament’s second chamber, with revelations about how a string of peers are benefiting from commercial interests.

One in 10 members have been hired to give political or policy advice, according to their own declarations, and others do paid work for companies that could conflict with their role as legislators. The findings expose weaknesses in the Lords code of conduct and raise questions about whether the rules on lobbying and paid employment should be tightened in line with restrictions signed up to by MPs.

Nearly 100 members of the Lords are paid to give political or policy advice by commercial firms.

A Labour peer offered access to ministers during discussions to sponsor an event in parliament.

A former minister has earned millions of pounds since entering the Lords by working for 30 companies.

Multiple peers are being paid by foreign governments including repressive regimes.

More than £1 in every £14 donated to political parties since 2001 came from those who have sat as peers in the last parliament.